WEATHER MADE CLEAR FOR ALL TO HEAR

"But seeing they could not See; hearing they could not Hear"
“The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Wednesday, August 18, 2010

Will Remnant TD5 Make a THIRD Visit to the Northern Gulf?!

RECAP OF YESTERDAY: Sea breeze generated rain showers and a few light thunderstorms (thundershowers?) were able to pop yesterday from around noon time through 2-3pm between US-1 and I-95 from North Brevard and points south. This activity was fairly isolated in nature and came to an abrupt end by 3:30pm as the east coast sea breeze worked further west toward the greater inland portion of the state. A diffuse, early evening west meets east collision occurred west of Orlando as anticipated with Lake County seemingly receiving the brunt of the rainfall when all is said and done. Moisture and a slightly veering wind profile at the mid-levels returned as anticipated in the post yesterday, but it was a dime late and a dollar short for areas on the east side of the peninsula to receive late afternoon activity, which was also expected, although there was less activity overall than was thought to occur. Today looks different though, and thus another morning of blogging is now at hand.
 
BY EARLY NEXT WEEK: See the end of this post.
 
SYNOPSIS: Not much of interest across the SE U.S. Remnant TD5  circulation center appears to be over NE portions of Louisiana at time and barely moving if at all. Surface and mid-level ridge axis of high pressure located over the southern third of the state of Florida. As such, a land breeze has developed along the Florida East Coast right at around sunrise. Mid-level flow at time seems to have backed at bit toward being from more of straight from the SSE-S rather than the SSW, but believe this is only temporary. Mid-level temperatures remain atypically warmer than what one should expect to exist for such a long period of time during the course of the summer, thus, thunderstorm coverage and intensity will again be downplayed.
 
TODAY: Virtually every model generated late last night through very early this morning is painting the same general picture.  The 850-700mb winds again appear as though the will veer toward the S-SW during the mid-late afternoon hours, with the GFS being the odd ball out and actually taking them the whole way around to being from the west.  I haven't seen the KSC sounding because unfortunately it's not available on the internet at this time, but other discussions, later water vapor loop, and early evening data indicate that atmospheric moisture in the mid-upper levels is in no way of short supply.
 
(EARLY TODAY):The east coast sea breeze will develop at what is now apparent to be a typical time frame, from 11:30am - 1pm. It will form earliest from near Vero and points south as well as right along the A1A corridor from near Patrick Air Force Base to the Cape.  With steering currents as they currently stand we could get some decent cloud lines of convective nature to form parallel to and over or along the intracoastal waterways between 11:30am -1pm which could grow into showers or even a low end thunderstorm (thundershower?) as the clouds lines organize into convective clusters. The greatest likely region as of this time that this seems will occur will be the same areas as yesterday. However, with the mid-level winds already in place (and less from an easterly component), they could form a little closer to the coast today than they did yesterday, which was mostly along I-95 or barely east of there in some locales. Some of this activity could actually penetrate the A1A corridor anywhere in Brevard (and perhaps Indian River County)...and all points north. Further south, where the sea breeze will have been established earlier in the day, storms should have a hard time making it east of I-95 except for maybe around West Palm Beach where a Lake/Sea breeze interaction could induce a storm or to very close to I-95 or even near US-1. One other scenario to watch for today is for storms to go up before noon further south along the earlier forming sea breeze front with subsequent firing of additional activity northward up I-95 to US-1 as we work into the early-mid afternoon time frame. Either way, the same areas will be affected by this pre-mid afternoon thunderstorm activity inherent to Florida summer weather.
 
(LATER TODAY): The sea breeze will have become established fully by 3:00pm and have begun its westward trek, however, it doesn't appear that it will make it much further west than the North Shores of Lake Okeechobee northward to thru Orlando and into Central portions of Seminole/Volusia Counties. The west coast sea breeze will also be making inland progression during this time frame. It again appears that a  diffuse  (less deliberate) collision of these two boundaries will not occur until around (or after) 6pm along or just maybe east of this aforementioned North/South line. The most likely area that it could actually occur more toward the east would be from a Kennedy Space Center toward Seminole County line. Storms/or perhaps storms debris could reach the immediate coast south of this line from near Indian Harbor Beach and points north, but of little to no consequence. The most likely region along the east coast to see a second round of storms as we work into the early-mid evening hours will be over the Kennedy Space Center, North Merritt Island, Titusville, Mims, Port St. John, Oak Hill ...and points north along US1 and AIA toward Daytona Beach Shores. Meanwhile, further inland much of Orange, Seminole, Volusia, Flagler...as well as further south over Central and Western Osceola and Okeechobee Counties will be prospects for storms. Most of the storms will be very slow moving...with apparent motion actually being induced by boundary interactions and propagation ...but in general storms will drift toward the North.
 
THURSDAY-FRIDAY: At time, it appears the low and mid level ridge axis currently near Lake Okeechobee will drift north to Central Florida. This would place inland portions to continue to be the favored area for late afternoon sea breeze collisions with some activity going up along or over the intracoastal water ways round noon time (give or take an hour either way)...but primarily avoiding the coast. The outlier area being the Space Center toward Mims and Titusville where the more eastward extension of land area gives them an added benefit of being 'further inland' than the region from Port Canaveral and south. Who knows, there could actually be a set up for a funnel cloud near the Space Center in this time frame.
 
SATURDAY-THIS TIME NEXT WEEK: By Saturday, the mid-surface level ridge axis will sink back south in response to a continental frontal boundary approaching  the Mississippi River Valley. It's hard to believe, but at this time remnant TD5 might still be barely hanging on at the mid-levels in this same region. In fact, and as strictly joked about the other day, it could once again end up being either displaced or redevelop further south along the Northern Gulf Coast somewhere just off the coast anywhere from Apalachicola toward Mobile. Although tropical development of this system is highly unlikely, this scenario could paint a continued wet pattern over already soaked areas from 2 previous visits from this same system. Just something to watch. Meanwhile, by this time next week we could be watching 1 or maybe even 2 tropical systems well off to the east in the Atlantic. In fact, by this time next week we could have our next named system...with another one about to be named on its heels.
 
Locally: The surface front approaching the Deep South, in conjunction with some mid-upper level troughiness, will be accompanied by lower thickness values in the 1000-500mb layer. This translates essentially to cooler temperatures aloft. As such, the period from Sunday or Monday through Wednesday could be characterized by stronger thunderstorms, greater coverage, and favoring the east side of the state. This will bear monitoring, since that would mean we might actually see some REAL THUNDERSTORMS  along the A1A corridor for the first time since official summer began this year.

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Tuesday, August 17, 2010

Low Rain Chances Central Portions Until Late Afternoon

RECAP: Pretty quiet day overall yesterday other than near Titusville, the Orlando area, and into Osceola County. There was an unofficial rain report of over 3" inches around Longwood but that seemed to be the highlight of activity.
 
NOW/SYNOPSIS: Low pressure near extreme S. Louisiana (remnant TD5) now over land and no longer a tropical weather threat other than enhanced afternoon thunderstorm activity for Southern and Central portions of Louisiana, Alabama, and Mississippi due to increased moisture and some veering of low level winds. Another very weak area of lower-mid level low pressure resides over the Western Bahamas and into South Florida. These two low pressure areas seemed to be weakly 'joined at the hip' across Central Florida and as a result surface and mid-level winds are very light. The morning KSC sounding taken at 6am is likely unrepresented for the most part of the air mass that will be over Central Florida late this afternoon into the evening hours and was disregarded for the most part. Water vapor loop showed a good slug of dry mid-upper level air has rotated into and across the region since day break. The seeming mid-level boundary across South Florida seems to be working slowly north though...and more moisture in the mid-levels should be returning to Central portions by 3-4pm  from the SSE-South. Additionally the low-mid level wind component which is now from the SSE-SE should veer ever so slightly to being from the S-SSW around sunset as the deeper moisture moves back in with this boundary with surface winds remaining generally from the SE-SSE.
 
TODAY: As a result (of the above stated) probably mostly dry most regions north of Vero for the early afternoon other than few renegade showers along the sea-breeze boundary north of Vero. Further south toward West Palm-Miami-Lake Okeechobee storms shouldn't have as much of a problem with getting started. In fact, the latest visible satellite animation I looked at indicated that showers and storms might already be beginning along the east coast down that way in the region closer to the mid-level boundary and thus greater moisture.
 
As we work into the mid-late afternoon mid-level winds to veer to S-SSW with an increase in moisture. By this time both the east and west coast sea breezes will have worked away from both coasts. Just exactly where they will meet is hard to say at this point...but as far as Central Florida is concerned any where along the west half of Osceola and Orange..and all of Lake County would be good bets for initial thunderstorm development sometime after 4:00pm. I am looking at the possibility of some early-mid evening activity beginning to flare up further east toward I-95 as outflow from storms further west coincides with the veering mid-level winds and increased moisture (although those will be very light and of not much influence).  Thus, we could end the day at sunset or shortly there after along the coast with some mid-level clouds and possibly remnant storm debris cloudiness (and a sprinkle)...particularly north of around Indian Harbor Beach along the coast.  As of the time of this writing, the best chance of 'near the coast'' activity for Central Florida appears most likely to be near Mims up toward Oakhill, through Daytona into Flagler County.
 
All in all, we could very well end the day much differently than from how it looks out there right now at noon. The big problem precluding development of greater storm coverage and intensity is persistent warm temperature ridging aloft which impedes the formation of stronger updrafts.
 
WEDNESDAY-FRIDAY: Remnant TD 5 and any barely existing mid-level troughing from the Bahamas and South Florida will likely be displaced by ridging to build in from the Atlantic and across these same regions. Mid-level flow along Central and North portions of Florida will remain light but general be from the SW-W and eventually NW as we head into Friday. However, it's unlikely this will dominant the overall steering flow or direction of storm motion. Looking for a greater likelihood of late morning activity to develop along the intercostals waterways up and down the entire coast line though with ample moisture once again (other than how it is as of mid-morning today)...with light west winds in the mid-levels and little if any sea-breeze in the early morning, activity could get juiced up..particularly Wednesday and Thursday shortly before noon time. Once the sea breeze sets up most activity will probably be limited to the I-95 corridor as far as the Eastern portion of the state south of Daytona Beach is concerned. We'll have to see how things develop during the course of the next 24 hours.  Likewise, with a slightly later sea-breeze development the coast will warm into the low-mid 90s temperature wise before falling back to the 88-90 degree range east of US1 by mid-late afternoon. Inland portions outside of showers and storms will remain in the 90s.

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Sunday, August 15, 2010

Possible Early-Mid Evening Storms For East Thru Southeast Florida

RECAP: No doubt about it, we got hot yesterday right along the coast before the sea breeze began around 1pm. The porch got up to 95F for a brief time. Most activity yesterday during day light hours was very widely scattered. It wasn't until after 6pm that the atmosphere seemed to get its act together for a mid-late evening show from Southern Volusia, various select parts of all of Brevard, and Osceola County down to near Rte 60. As anticipated the steering flow shifted to being from more of a NNW direction after sunset, as such some of the storms paralleled right down the A1A corridor from Cocoa Beach south and further inland over much of the south half of Brevard. The strongest storms were found over SE portions of Osceola County with other storm over extreme Southern Volusia and North Brevard. Wish this had all happened during daylight hours as a beautiful gust front was visible approaching from the north in Cape Canaveral during lightning flashes as a decaying area of storms descended south from Volusia and over the Merritt Island Wildlife Refuge between 9:40-10:30pm. Would have made for a nice photograph. Included in this post is the radar image showing the dying storm just of where it reads "NASA". Shortly after this image was saved the storm had gone all green and lightning quickly abated in full.
 
TODAY: In sort of a quandary this morning since the 6AM KSC sounding came in suspiciously on the dry side with a PWAT of only 1.60" where as Tampa is over 2.22". Other little problems exist for much of East Florida from Daytona to Miami as well. The steering flow remains from the W-NW but is very light ...generally 10kts or less which would be much less likely to inhibit greater inland progression of the east coast sea breeze by mid afternoon. Additionally, an elongated cluster of showers and thunderstorms roughly over the Gulf Stream region in the Atlantic well off shore is spreading patches of high level cirrus over the coastal communities due to easterlies up at the jet stream level of the atmosphere. However, these clouds seem to be thinning with every passing hour since early morning over the Central and Northern portions, but appear to soon be on the increase further south especially from Ft Pierce on down the line. This could put a damper on late day thunderstorm activity around Lake Okeechobee under what would otherwise be the most likely region to see storms today. Perplexing. The NWS offices for this portion of the state are officially calling for a pretty good coverage of lightning storms later today down there with the possibility of waterspouts over the Big Lake or the intracoastal, but I'm not totally sold on that notion at this point. If I lived down there I'd be monitoring the sky for increasing high level cloudiness...the more of that there is the lesser the chances of storms...at least until early evening. Additionally, mid-upper level temperatures remain on the warm side which would result in later shower/storm initiation for the most part as well as preclude activity from being overly strong. But not to minimize, ANY lightning is dangerous lightning...and some of those storms last night were pretty active with it but not excessively so. Remember, it does not have to be raining at all to get a lightning strike right near by! It happens all the time.
 
Closer to more central portions of the state, the east coast sea breeze should start no later than 1pm (if it hasn't already while I'm typing this) ...I also am pondering the possibility that it will be somewhat more enhanced once it gets going (by 2:30-3:00pm) than one would normally assume due to out flow from collapsing storms that have been ongoing near the Gulf Stream region since very early this morning. Which reminds me...that region out there will need to be monitored CLOSELY during the next 24 hours for signs of a mid-level if not surface level low development (weak in nature)...which could eventually move in on the Florida East Coast.  This is near the same region that the old mid-level (and once surface frontal boundary) was residing just to the north of here yesterday. Otherwise, a diffuse west coast sea breeze seems to just now developing which will move inland during the course of the afternoon.  Very little activity (even less than yesterday at this time) is occurring over portions of North Central Florida.
 
Do not believe we will see any showers or storms along the developing East Coast sea breeze during the early afternoon hours other than a few sparse showers from Jupiter Inlet and points south along and west of I-95.  Given that the deep cirrus deck has not yet moved in on the peninsula down that way, the other wild card in the deck is for the possibility of Lake/Atlantic Breeze boundary collision to occur anywhere along east sided shores of the lake before 3pm. Other than that....
 
Later today and tonight. Believe that overall shower/storm coverage over the peninsula will be on the 'lowish' side, at least initially until the 4-5pm time frame at least. After max heating and thus peak atmospheric instability has been reached storms could begin to form in earnest along either the west or east coast sea breeze boundaries. Much of things again will be contingent upon whether that high cirrus deck of clouds penetrates in on St. Lucie County and further north as well during the course of the mid-afternoon.  Believe when push comes to shove that the east side of the state will eventually be the favored area for development anywhere from Jacksonville to Miami...could very well end up seeing a repeat of last nights show.  Granted, that's a tough pill to swallow so mostly just throwing that one out as a possibility and not an apparent likelihood.  Also note that I wrote this would be "the most favored area"...that's if and only if the cirrus doesn't move in and/or the east coast sea breeze doesn't suddenly start to make a bee line to the west during the mid-late afternoon.
 
TROPICAL TYPE WEATHER?: There's been a lot of conjecture about what good old TD5 is going to do in the next few days. Right now it remains a remnant low which now appears to be centered close to the Alabama-Georgia Border in the southern portion of those states, however latest radar loops and surface observations indicate that it may relocate to somewhere WNW of Panama City on the Florida Panhandle. There has been much talk in the weather world about this system regaining depression and maybe tropical storm status. At this point, I'm thinking it just MIGHT become a depression once again if it can sustain enough (if any) time and distance over the Gulf waters and away from the coast.  I'm thinking that this will not be the case..but the mid-level low associated with this system could actually get its act together good enough to provide the Gulf Coast region from the Florida Panhandle-Alabama-Mississippi-Louisiana with some serious rainfall totals when all is said and done. There could be a return visit for the Louisiana Big Toe area. In fact, this entire system could get caught up in an approaching trough and be dragged over the same areas it visited the past few days - a full loop-de-loop. Supposedly, it will eventually get caught up in the trough and be history..but I'm not even sold on that notion! It could revisit again in another loop. Fun to watch and speculate over in any case.
 
But what about off the Florida Coast as mentioned above? As mentioned earlier, some form of tropical activity could be in the making 100-200 miles off the Florida East coast during the next 12-36 hours. We'll have to watch this as it could have a significant impact on the weather from any where from Flagler County south to Dade County from late Tuesday night through Wednesday...so for now..the reality of the situation is that that time frame is up for grabs. (as he thanks the fact that this is an unofficial blog post and can get away with 'forecast murder'). Said in jest of course.
 
More to write about tomorrow but watch the sky in a NW-N direction today, particularly as we approach the early evening hour!

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Saturday, August 14, 2010

More of the Same Today for East Central Florida

(Image: Atlas V Rocket Launch This Morning from KSC)
RECAP: Weather evolved pretty much as expected yesterday, with the strongest activity over Central Orange county this time rather than over Osceola County as it did on Thursday evening. Rain showers also dotted much of the landscape, even along the immediate coast, from Patrick AFB up to Jacksonville, with one lone thunderstorm SSW of West Palm Beach during the early evening. Maybe not quite as much coverage today, but locations will be pretty much be the same as yesterday with one or two good lightning producers in the offering later this afternoon most likely inland. Oddly, a brief waterspout was reported by a pilot offshore Key Biscayne within the past hour from a mere cloud line. The Miami radar is currently in 'clear air mode' which I find humorous. Talk about unexpected.
 
SYNOPSIS: Strong high pressure continues to push down the U.S. Eastern seaboard behind a frontal boundary whose southern most extent seems to have penetrated into east central portions of Georgia. Otherwise, disorganized area of low pressure persists along the N. Gulf Coast region, seemingly centered inland now near Clanton, Alabama or SSE of Montgomery.  Over the state of Florida a weak bubble of high pressure was located right along the east coast of Central Florida near sunrise, but during the past 2-3 hours that seems to be retrograding west toward the Gulf. Aloft, mid-level winds are generally from the west at 10-15mph and PWATs are even lower than yesterday but still within a reasonable range for shower/storm development. In the upper levels winds are light easterly, and as a result some very high, thin patches of cirrus clouds are passing over way up there from off the Atlantic.
 
TODAY: The winds along the coast near Canaveral and PAFB were nearly calm initially, but have since sunrise picked up a bit from the west as the land-breeze finally began to small degree in this region right after sunrise. A sea-breeze might have already begun down by Miami which is what would have help produce the waterspout (perhaps). Believe the delayed land-breeze might have partially been due to a surface high over the region. Winds at around 8-9am finally have been felt from the west, but only ever so lightly. There is significantly less shower activity up in North Central portions of the state than at this same time yesterday, with the only precipitation near the state being over the Panhandle. None in the GOM or over the Atlantic waters.  Mid-level winds are still from the west a bit weaker than yesterday, but those could very well veer to more of a WNW-NW direction by later today. Atmosphere not abundantly saturated, and warm mid-level temps (around 11C at 700mb and -5 at 500mb) not much different from yesterday.
 
Local WRF model guidance as well as the latest RUC are both indicating an earlier start to precipitation today along the immediate east coast, perhaps due to the fact that the sea breeze should start a little earlier with the slightly weaker west winds aloft; I'd guess onset would be between 11am-noon (if not sooner) rather than between 12pm-1pm. The earlier onset would jive with the slightly weaker westerlies directly overhead this morning. As such, showers could form anywhere from the Daytona region south to perhaps as far south as Melbourne east of I-95 between 1:15pm-2:15pm and creep in toward the coast, especially between the Space Center and Melbourne Beach. Further south showers might have a hard time reaching the coast or even forming for that matter due to even weaker westerlies aloft which might never actually overcome the sea breeze induced easterlies today at anytime (i.e., especially from Sebastian southward to Miami).  As such, any activity to go up today south of somewhere between Melbourne Beach to Sebastian will likely remain west of US-1 or even I-95.
 
But in the more likely areas to see rain (north of Melbourne Beach) there could be several chances for a rain shower anytime from around 2pm - 7pm.
but lightning chances for this activity will likely be low-end. However, inland could be a different story where greater instability will be realized due to greater (prolonged) surface heating over the landmass.  The west coast sea breeze might be a little slower at working across the state than the past two days, but eventually by 6pm it could reach east of Orlando. In should be noted that the past two days the west coast sea breeze progression has been very tricky and has pulled a few fast ones on us (mostly due to convective outflows from activity that went up along its leading edge).
 
But putting that possibility aside, activity should go up along and ahead of this boundary after 3pm, particularly from anywhere north of Central Osceola County to the Georgia border while any coastal activity that might have happened to form earlier will wane.  Collapse of these stronger inland storms, particularly over Orange, Eastern Lake, Western Volusia and Seminole Counties could accelerate the west coast sea breeze toward the east very late in the afternoon into the early evening...particularly from Indian River County up toward Cocoa Beach. Some areas, particularly near Rte 60 in SE Osceola County north into SW Brevard where much of the area could have remained rain-free (and thus still more unstable) might see an early evening thunderstorm as well.
 
Another area of interest to monitor will be along the northeast  through southeast shores of Lake Okeechobee where earlier sea breeze onset could work with the Lake Okeechobee lake breeze. Any ensuring collision down that way could give rise to a storm somewhere around Palm City to Green Acres, or over the Arthur R. Marshall Loxahatchee National Wildlife Refuge...all areas west of I-95.
 
SUNDAY:  The weak frontal boundary off the Georgia coast will work a little further south of the NE Florida Coast and diffuse as the ridge axis across South Florida breaks down a little with one portion retrograding further into the Gulf and eastern portion off the SE Florida coast. This will leave most of the peninsula in a very weak pressure pattern with perhaps a bit of a NNW-NNE flow aloft, albeit very weak. Therefore, expect most activity at this time to be limited to be sea/lake breeze collision driven over inland areas. But note, some numerical models are indicating better chances of rain tomorrow, but my thinking at this time is that those chances will come on Monday, if at all. One more reason for needing to make a blog post tomorrow I suppose.

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Friday, August 13, 2010

Photocopy of Yesterday (Pretty Much)

(Image: Rain shower over the Beachline (528) as it moves over Cocoa, FL heading toward Port Canaveral yesterday)
 
RECAP: As was expected, yesterday was almost null of thunderstorms over South and Central Florida other than a boomer over NE Osceola County in the early evening which died as it headed toward the Brevard County line. Other than that one, there was a wide 'sparcity' of rain showers which moved off the coast from near Satellite Beach up to Jacksonville. The sea breeze over Central Florida never reached much further west than I-95.
 
SYNOPSIS:  Not much change from yesterday with surface-mid level ridge over South Florida and frontal boundary pulling off the NE to mid-Atlantic U.S. coastal region. Higher pressure is building south behind the frontal boundary to somewhere hear the N/S Carolina boarder region. Locally, we have the high pressure axis over south Florida but the upper level high appears to be forecast to be located very close to East/Central Florida or just off shore by sunset.  Already, the KSC sounding is showing dryer PWATs today...but with a slightly veering wind profile aloft from yesterday (mainly from west to east). Additionally, the 500mb temp is about a degree or two cooler, but then again the mid-level temp. is a degree or two warmer.
 
The only the notably different from yesterday is that there appears to be an earlier onset of very widely spread rain showers pushing across N/Central Florida and into the immediate Central portions (like the Orlando area) as well as of noon.  With a westerly steering current of about 15kts just above the surface we are getting just a little later than normal sea-breeze onset, but with PAFB already having gone light and variable..the sea-breeze will be in session from around KSC and all points south by 1pm.
 
TODAY: With the sea breeze having begun from at least near Cape Canaveral and points south by 1pm and continued prevailing westerlies not far above our heads..believe the sea breeze will again have a hard time reaching much further west than I-95 as far south as perhaps Vero Beach. My initial impression from visible satellite imagery animation is that the west coast sea breeze has already worked into far Western Orange and Osceola and Lake Counties, placing its arrival to the east coast or along I-95 from Titusville south in the 3:00pm near Titusville to about 5pm down by Vero Beach time frame (and possibly even up to an hour earlier than that)....and all points in between sometime between those two times.  The breeze is not as enhanced as it was yesterday, as yesterday it had earlier west coast storm outflow to give it an additional shove. Rain showers are depicted along the west coast sea breeze though as I write as it heads from west to east seemingly unimpeded by the light easterly winds up at max rain shower top levels as shown by the cirrus streaking back opposite the direction of motion.  Storm motion will initially be from West to East but may veer by late in the day to more of a WNW-ESE direction.
 
With all said, today should be pretty much a carbon copy of yesterday as far a rain storm intensity and locations goes...but perhaps eventually affecting a larger area of real estate from Tampa east to near Melbourne Beach and all areas north of that line, with all areas from Orlando east best being impacted noticeably earlier.  With the earlier time frame, can't discount some renegade storms forming just about anywhere well behind the west coast sea breeze as we work into the early evening hours...mostly north of a Vero Beach - Tampa line. I am interested to see what will happen along the immediate East Coast from Cape Canaveral to around Melbourne Beach late in the day, particularly if the mid-level winds due indeed veer at all....this could give storms an extra boost and slight turning in the mid-levels if this does occur.
 
Further south, I'm somewhat in a quandary as to what could happen south of Vero. The models as well as the Storm Prediction Center are indicating precip. as far south as Miami from I-95 and west of there  by very late in the afternoon, but sounding data and current radar/satellite trends are not hinting at this to occur. Thus, interested to see what occurs over the region bounded by St. Lucie, Okeechobee, and Palm Beach Counties later today.
 
TOMORROW: Not much exciting to discuss. Looks like the east coast sea breeze will have an earlier initiation time for almost all of the Florida Coast with not as much of a push back toward the east during the mid-late afternoon hours as mid level winds weaken. Therefore, believe most rain activity will be limited to inland areas for most of the peninsula. We'll have to recheck on that during the course of a couple more model runs to see what evolves before posting tomorrow morning though.
 
SUNDAY-MONDAY: So far this time frame is looking pretty darned uneventful for the East Coast if not most of the peninsula as far as robust thunderstorms goes...will have to watch to see what happens to a somewhat mid-level backdoor boundary being shoved south off the U.S. East Coast by ridging to the north..as well as how that boundary interacts with lingering low pressure over the N. Gulf Coast region. Lots more will be revealed, but for now I'll suffice it to say that nothing remarkable is in the makings for the next 2-3 days. Also to watch for may be a mid-level low to form north of the Bahamas at the tail end of the mid-level trough as the remaining portions of the trough push off well into the Atlantic.
 
 

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Thursday, August 12, 2010

Possible Showers/Storms For Central-North Portions of Florida

SYNOPSIS: Low pressure remnant TD5 resides near the big toe of Louisiana this morning with little forward motion detected. High pressure developing in its wake over South and Central Florida well out into the Atlantic to the east, the axis of which appears to be running east-WSW across the state near South Brevard County toward Ft. Myers. Moisture throughout the atmosphere not as abundant as the past few days, but ample enough for showers and thunderstorms, particularly where moisture convergence occurs with boundary interactions between lake/sea breezes. Steering through the column is generally from the SW across the north half of Central Florida and further north (where the greater moisture also resides).
 
TODAY: Expect the west coast sea breeze to make an early head start late this morning, whereas the east coast sea breeze will have a hard time being established north of somewhere between Melbourne and the Space Center. Delayed sea breeze at least north of Melbourne toward Oak Hill will permit late morning temperatures to be quite warm. Warm mid-upper level temperatures and lack of boundary convergence will likely inhibit late morning convection significantly along the intracoastal. By mid-late afternoon expecting showers and isolated thunderstorms to have developed mainly north of a Melbourne to north of Okeechobee line and points west from near Sarasota north. All activity will move toward the NE-ENE..and be somewhat enhanced as it roles in from S. Osceola county and points north, particularly where there are interactions with the sea breeze. After an afternoon of plentiful sunshine across much of the peninsula, instability levels will maximize after 4:30pm after daytime heating. Boundary interactions will likely be maximized after this time as well since surface winds in the aforementioned areas south of Melbourne (the sea breeze) is strongest. A low level wind shear axis could be established as well where convergence is maximized...much like yesterday where the prevalent SW flow over-runs the sea breeze boundary...so some funnels could be possible under the deepest updrafts. Not really expecting robust lightning producers though, with greatest coastal rain chances for the east coast from around Cocoa Beach and points north of Daytona toward St. Augustine.
 
DAYS AHEAD: Having to quickly broad-brush this portion this morning due to time constraints, but models are trending toward leaving a somewhat chaotic area of low pressure along the N. Gulf Coast region for nearly a week. In the meantime, high pressure to build southward along the U.S. East Coast and forcing somewhat of a "backdoor" cold front down the eastern sea board ahead of it in the next couple of days as the surface and mid level ridge of high pressure remains over S. Florida. Moisture levels not overly impressive under a continued W-SW steering flow regime with warm temps. aloft, precluding widespread thunderstorm activity...or storms of notably strong intensity. Temperatures will likely remain on the warm side (a few degrees above normal) for much of the state other than extreme SE portions along the coast south of West Palm Beach. Eyes will undoubtedly be focused on the N. Gulf for future development, but at this time it does not look like any development there would be of solely tropical nature. Thunderstorm activity will remain at generally normal to just below normal levels.

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Monday, August 9, 2010

Lull in Rain Activity for Central Florida - More to Come?

RECAP: Early in the day rainfall yesterday produced rain amounts over 2.00" in many locales. In Cape Canaveral we received 2.19" bringing the total from Friday and Saturday up to exactly 5.00". So much for a local drought...since more could be on the way. There was a waterspout reported offshore Clearwater, FL yesterday, but most active weather reports outside of rain were wind gust reports from storms near Patrick AFB, Cape Canaveral, and Lake Okeechobee (just to name a limited few) which were in the 40-45mph range.
 
SYNOPSIS: This morning it appears a weak surface low might by located just off shore the East Coast NE of Cape Canaveral, but equally low surface pressures are being measured on land areas as far south as West Palm Beach. At the mid-levels low pressure seems to be taking shape somewhere over extreme SW Florida whereas in the upper levels it is most discernible over the West Central Bahamas well offshore Ft. Lauderdale. So as we can see, it is a very disorganized and broad area of low pressure that is in the cards for today. Some drier air in the upper levels wrapped around the front side of the upper low after the passage of yesterday's rains, but that area of 'dryness' has thinned out and is moving out from the Northeast portions of the state. The mid-low levels remain very moist though, and as such many areas are reporting light fog and low cloud ceilings as of 8am which will likely burn off by 10am.
 
TODAY: First off, and amazingly, little change in forecast thinking from yesterday's post.  Believe that with some daytime heating the surface low will eventually move right on to the coast initially but then relocate somewhere west of Ft. Pierce (or in the Lake Okeechobee region) closer to the mid-level low which seems to be near SW Florida at this time.  Winds will remain light most of the day but assume a general easterly, sea breeze type direction and rain chances along the coast north of Vero could remain pretty low most of the day, but heating of the day (by early-mid afternoon) will more assuredly have more to reveal. But as of this time, expect that any significant rains to fall most of the day will be across the state from Ft. Pierce, south. Particularly just south of West Palm Beach, through the south half of the Lake Okeechobee region, all of the Florida Keys, and to just north of Ft. Myers on the west coast. There will remain the threat of waterspouts and thunderstorms in this same region.
 
TONIGHT: The surface, mid, and upper level lows will begin to coalescence into 'somewhat' more of a concentrated area somewhere just west - southwest of Lake Okeechobee after sunset and continue to organize slowly and somewhat chaotically more so over night as the upper low near the Bahamas moves generally west and perhaps a bit south of that same location.  As such, a stacked gradient midlevel flow behind all of these systems from the E-SE will increase along the east coast of the state from near Flagler County - Indian River County with Brevard in the central locale for strongest winds aloft at all levels from about 8,000 ft to around 18,000 ft (at least).  This deep, stacked gradient flow (note, I didn't say 'low') should advect even more moisture through atmospheric layers into East Central Florida originating from the Bahamas beginning post-sunset and through all of Tuesday.  Surface winds shouldn't be that big of a deal since the surface low will remain weak...but as moisture, and thus rain chances, increase downdraft winds from rain showers could be noticeably gusty. I see rain chances for tomorrow as shown on The Weather Channel as well as numerical models are already indicating a 60% chance of rain for Tuesday, but wouldn't be surprised to see that number boosted upwards for portions of Central and South Central Florida by tonight if the above conditions develop as stated. Temperatures aloft will remain on the warm side though, so robust thunder and lightning is not expected. However, we'll have to continue to monitor the situation for the possibility of land falling waterspouts with the heaviest rainstorms, particularly on Tuesday.
 
TUESDAY: I'm painting a worst case scenario for this day.  If conditions do develop as noted, then Tuesday will be a good day to keep an umbrella handy. Rain showers could move onshore from the Atlantic at just about anytime from sunrise-after sunset well into the evening toward early Wednesday. Minor street flooding would be possible where training of fast moving rain showers and possibly some thunder occurs anywhere from near Daytona to West Palm Beach. Keep tuned into your favorite media outlets by this evening to see how things are developing (assuming they do).
 
WEDNESDAY: Again, no change in thinking. This will be a transition day. It appears the low pressure system will become a bit more organized and move west-northwest to passage almost directly over the infamous oil-spill region toward the coast of Louisiana or perhaps Mississippi. High pressure will weakly reassert itself across the state as gradient flow at all levels significantly abates and shifts toward more of a southerly direction during the day. Normal diurnal sea breeze/lake breeze convection anticipated with most of it likely remaining just west of the US1-I-95 corridor over Central Florida but almost anywhere for the southern third of the state.
 
THURSDAY-SUNDAY: High pressure ridge axis to slowly sink south toward the southern tip of Florida as a large low pressure area NE of the Great Lakes region and associated mid-low level trough takes shape down the Appalachians. Mid-level flow will be from the SW-W while surface flow will remain weak, permitting daily sea breezes on both coasts to form. Rain chances will return to around the 40% range...but shower/thunderstorm motion during the mid-late afternoon will be slowly toward the east side of the state, with early morning-early afternoon activity developing along the west side.

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Sunday, August 8, 2010

Elevated Rain/Storm Chances Through Next Sunday for East Florida

RECAP: It's been interesting the past two days for East/South Florida the past two days. A funnel cloud near the Space Center, waterspouts over Lake Okeechobee and offshore West Palm Beach, and weak EF-0 tornadoes in Boca Raton and New Smyrna Beach. Also some locally heavy rainfall here in Cape Canaveral with 2.81" recorded over a very small area yesterday from a slow moving back-building cell just south of the Cape. More is in the offering to various degrees for portions of Central and especially South Florida (south of a line from Ft. Pierce on the east coast to Port Charlotte on the west coast) through Tuesday!
 
SYNOPSIS: The quasi-stationary boundary discussed yesterday that was in S. Georgia seems to have sunk into N. Florida and is now south of I-10. It currently appears to be just south of St. Augustine-Gainesville. It should sink  further south during the day to near Daytona or even Oak Hill by sunset. Meanwhile, a complex area of low pressure from the surface to the upper levels is developing from the Bahamas-across Central/South Florida/eastern Gulf of Mexico and along the Florida W. Coast from Tampa and points south.  The ridge axis that has the bane of our dry existence for Central Florida all summer seems to have sunk toward the Florida Straits and is pretty much out of the picture for the next two-three days, at least.
 
TODAY: Plentiful atmospheric moisture (PWAT above 2.0" all locales) combined with the weak surface boundary to the north as stated in the 'synopsis' portion, combined with an early afternoon on set of the East Coast sea breeze and instability with heating of the day should once again provide the dynamics for some decent rainstorm/thunderstorm coverage particularly south of a line from Daytona Beach on the east coast to west of Brooksville on the west coast of the peninsula. There is a very persistent area of storms well off the Central Florida east coast near the N. Bahamas which has been there for over 24 hours (which is perhaps a sign of things to come).  This area is moving slowly south..and may be 'coupling' with another disturbance along Florida Gulf Coast on the other side of the state. Light west winds this morning should give way to a sea-breeze boundary around noon time which probably won't even make it as far west as Orlando area due to deep (but somewhat weak)westerly flow aloft.  Expect spotty showers/storms to impact the east coast as early as noon time, considering there already is a small shower near Daytona as of this writing. Initially motion of activity will be from the W-WNW but may very well swing around to more of a NNW direction by mid-late afternoon from Sebastian and points north as an area of low pressure becomes more organized at the surface and aloft.
 
It must be noted that chances of rain along the east half of Central Florida is totally contingent upon where the low pressure at the mid-levels finally organizes during the course of late this afternoon and into the overnight hours. Thus, rain chances could go from very high to very low by late afternoon...for now it's probably best to err on the wet side until morning model runs and radar/satellite trends are established. There are hints from local the local WRF that all rain activity will be shunted toward the SW-W Florida side of the state by late afternoon...leaving East Central Florida rain free.
 
(Possible active weather today as well: Although not expecting especially strong thunderstorms today YET due to 500mb temps around -6C there is always the ever present threats from cloud to ground lightning. 700mb temps have dropped maybe 1 degree since days of late..and an additional one or two degree drop could occur during the course of the afternoon if indeed low pressure starts to develop over or near the state...this bears watching since this if it does drop that would provide a boost to storm activity later in the day. Additionally, the threat for funnel clouds and waterspouts (some which may becoming land falling), particularly on the intracoastal and near shore Atlantic waters remains ever present at almost any time after 1pm for the entire Florida east coast from the Cape to S. of Miami).
 
MONDAY-TUESDAY: As stated above, everything is contingent upon where low pressure organizes. It currently appears to me that a weak surface low may end up actually developing right over the peninsula west of Ft. Pierce with the mid-level low forming just east of that location sometime overnight into Monday. This will be a pretty broad and disorganized area of low pressure though, and will affect a broad expanse of real-estate. Particularly from Ft. Pierce and points south around the tip of South Florida and up the west coast near Pt. Charlotte and everywhere across the peninsula between those locations. Outside of this zone, the region further north to a N. Brevard County to N. Hillsborough county line will also be in the pot for enhanced rain chances, just not as much so as those areas further south.
 
As the area of low pressure organizes and moves generally westward into the Gulf there may actually be a complete lull in activity along the east coast north of Vero Beach, but then as the low moves further into the Gulf and high pressure builds in its wake a deep SSE-SE flow will target East Central Florida, namely Brevard-Indian River-St. Lucie County...sometime late Monday into Tuesday. Thus, after a lull later tonight and Monday rain chances could climb on Tuesday.
 
WEDNESDAY: Transition day as the low pressure area moves further away and high pressure begins to reassert an influence. Thunderstorms likely in a generic summer pattern.
 
LATE THURSDAY-NEXT SUNDAY: Ridge at the surface and aloft still appears as though it will reassert itself over S. Central Florida (as mentioned yesterday) around the latitude of the South Shores of Lake Okeechobee, if not further south than that as another front and mid-level trough deepens down the U.S. East Coast. As a result, steering flow from the SW will commence in this time frame favoring the west side of the state for morning - early afternoon storms and central and eastern portions of all of Florida from early afternoon into the evening hours.

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Saturday, August 7, 2010

Wet Periods Ahead Through Tuesday, Finally!

SYNOPSIS: Surface frontal boundary off the NE and Mid-Atlantic coast curves WSW-W and onshore and is strewn across Southern Georgia this Saturday morning.  This boundary will sag further south toward the Florida/Georgia border by this evening as high pressure builds in behind it.  At the same time, a high pressure ridge axis is extended south of this boundary general in east/west fashion south of the peninsula in the vicinity of the Central  Keys into the SE Gulf.  The gradient flow between these two systems from the surface up to 15,000 ft is from the WSW to W in the low to mid and becomes more from the NW at upper levels.  Abundant tropical moisture at all levels is being depicted by both the Tampa and KSC sounding data.
Also shown by satellite imagery and by looking outside is considerable high level cloudiness which is being advected across the state from the ENE-NE from convection well off shore in the Atlantic east of Jacksonville to South Carolina.  Rain showers are increasing in coverage across western portions of North/Central Florida which are moving toward the east and approaching Lake County.
 
TODAY: Not much change overall in the synoptic features other than that the frontal boundary in South Georgia will sink further south by late afternoon toward the Florida border. A definitive west to east steering current for showers and thunderstorms is well entrenched and will remain as such throughout the day. As such, the afternoon sea breeze will have a little bit of difficulty developing, but believe it will form south of the Cape but will remain only 10-20 miles west of the coast at most where it does develop. North of the Cape the sea breeze might not develop at all.  Early day high level clouds will keep the temperatures from reaching their highs of mid 90s at bay and into normal or just below normal levels...and also preclude anything more than isolated late morning showers from forming over the intracoastal waters.
 
Between early to mid-afternoon the shower/thunderstorm coverage now impinging on North-Central Florida will increase in coverage with other activity developing pretty much anywhere over the peninsula, particularly around Lake Okeechobee and maybe (but not as much so) over the Kennedy Space Center/Titusville region.  These two locations yesterday are where a funnel cloud was sighted (near KSC) and a waterspout was filmed (Lake Okeechobee).  Assuming the sea breeze does form south of the Cape (which would be around 1pm)...additional storms will form near the immediate East coast at that time over/near the Indian/Banana Rivers.  Additionally, as we work into the mid-late afternoon...the west coast sea breeze will push across the state. That, combined with outflows from earlier inland storm activity...will increase coverage to a broad expanse of rain and thunderstorm activity over the east 1/2 of the state by late afternoon.  Exact locations as to where the strongest activity will occur is almost impossible to determine at this time of the morning given the current/broad synoptic set up of uniform conditions.
 
Late afternoon-mid evening.  Activity will be begin to wane from West to East as activity moves off shore and much of the atmosphere has been worked over by the storms of the day light hours.  Additional isolated storm activity is possible though over extreme eastern portions and around the Big Lake through 9pm...especially further south around the Lake.
 
SUNDAY-TUESDAY: Leaving tomorrow open for another day's discussion. But will suffice it to say, just for now, that similar conditions appear to be likely as today.  Big changes could be in store though beginning over night Sunday through all of Monday and into Tuesday.  Models are not in any form of agreement as to the details of the upcoming scenario..but do agree in general that a mid-upper level low which is currently NE of the Bahamas will retrograde in a general westward fashion and toward the peninsula...or that another one will form very close to, if not over, the state during this time frame near the base of the mid-level trough just off shore.  Unlike over a month ago when a frontal boundary stalled over the state and precipitation forecasts were high and all we got was mostly cloudiness I do not believe this will be the case this time.  Wherever the center of low pressure develops we will also have pockets of mid and upper level vorticity (a trigger) rotating over the state, particularly south of line from Jacksonville on the east coast to Crystal River on the west coast.  It is also worth mentioning that SOMEBODY could be in for a 'rain event' of sorts somewhere along the East coast..anywhere from Daytona to Miami.  This would likely come in the form of flat out rain with some imbedded thunder thrown in....but seeing as how the parameters for such an event have yet to even develop this is worth only a broad brush possibility mention at this time.
 
Again, the models do not agree at all on the specifics..but do agree on generalities. They also agree that whatever does develop should be out of the picture and west of the state by Wednesday.  These mid-upper level features are very difficult to predict at this time of year when the jet stream is well north near the Canadian border...they seem to have a mind of their own.  Who knows, the region of question which is forecast to develop might move slower than forecast and linger into parts of Wednesday (but at this time that scenario does not appear likely).
 
FRIDAY-NEXT WEEKEND: After a brief interlude of rain activity as the synoptic features transition (Wednesday-early Friday) it currently appears that the Atlantic ridge of high pressure will re-establish somewhere across South/Central Florida to Central Florida with abundant moisture remaining in place. The exact placement of this ridge will determine shower/storm motion in the future and what areas will be most likely to receive afternoon and evening thunderstorms.

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Thursday, August 5, 2010

Rain Chances For The Eastern Florida Coast Improve A Bit

After a few blog days off figured I'd dig in to a 'forecast' for the next few days as things look a bit more interesting for the next few days. The mid-long range models have been depicting the upcoming scenario to unfold for a couple of days and they are coming to fruition as I write. Details to follow below. Otherwise, the insane heat over parts of Alabama, Mississippi, and Tennessee (to name a few) might come to an end for maybe two days as a front in this region will increase cloud coverage and storm activity.  I noticed the past two days that a few isolated locales in Tennessee had heat indices exceeding 120F degrees...UGH.
 
SYNOPSIS: Trough of low pressure and associated cold front is digging SSE-ward along the U.S. eastern seaboard this morning and will continue to do so through Friday. There was a tornado warning for a spot in Connecticut this morning ahead of the front, and active weather from New England, Pennsylvania, New York and into Virginia, Kentucky, and Tennessee will experience additional activity as the front moves in.  As such, a ridge of high pressure that has been north of the area has shifted sufficiently south to now be located almost directly overhead Central Florida late this Thursday morning. By this evening...the ridge should be located somewhere between Sebastian-Vero Beach along the east coast and over Tampa Bay on the west coast. Steering winds will be close to nil...but assume a slight S to N or even SSW-NNE component somewhere around sunset this evening.
 
TODAY: East and west coast sea breezes should have no problem developing during the mid-late morning hours and progress inland from both coasts. With plentiful moisture in the atmosphere coupled with the normal summer instability with heating of the day rain showers and thunderstorms can form anywhere just west of the coast from Brevard south to Miami where sea breeze/lake/outflow boundaries interact..more likely near the coast the further south one goes earlier in the day, particularly south of Ft. Pierce. By mid afternoon most of the activity will be located along and west of I-95 except down around the Lake region where a Lake/sea breeze interaction is possible along the north and northeast shores of the Lake.
 
Late afternoon is somewhat up for grabs. As the aforementioned ridge is forced further south a more south to north or even a bit toward the east steering flow could develop as inland storms' outflow keeps interactions pinned along or even just east of the I-95 corridor, especially from Melbourne and points north into Volusia and Flagler Counties. The result might be some storm debris showers or just cloudiness as we head toward sunset over the A1A corridor...better than nothing.
 
FRIDAY: We should start out with a land-breeze right on the coast tomorrow morning with the surface ridge axis up through 700mb located south of Brevard County. Gradient flow won't be strong enough to overcome a slightly delayed sea breeze by around noon time...so the coast could warm up just a bit more in the late morning time frame before the sea breeze comes in. Steering will again be from south to north or even a bit toward the NNE-NE throughout the day. Thus, like today...the coastal communities, especially those north of Sebastian and more so further north into Volusia County could actually experience a full bore thunderstorm anytime from mid-late afternoon.  Also, some late morning-early afternoon thunderstorms could form along the sea breeze boundary along the US1-I95 corridor from Titusville and points south. I'd say at this point that Friday will be the best chances for the immediate coastal communities like Cape Canaveral, Cocoa Beach, Satellite Beach, and Indian Harbor beach to get truly measurable rainfall and some lightning.
 
SATURDAY-MONDAY: Trough of low pressure to the north...somewhere around Central Georgia on its southern most extent...begins to get more diffuse as high pressure builds SSE from the northern Plains region into the Mississippi River Valley region.  The ridge of high pressure over south Florida also becomes more diffuse...this places Central Florida in a very light, ambiguous wind pattern aloft leaving the door open for inland boundary interactions to the be sole focal point for afternoon convection, although late morning to just post-noon time activity along the intracoastal waterways will be possible as well with the westward moving sea breeze as it moves in. The GFS is hinting at an inverted trough moving in from the east on Monday which would greatly enhance rainfall potential for all of the east coast of the state...for now this will just be monitored for possible development as I see no reason for this to occur at this time.
 
TUESDAY-THURSDAY:  The trough of low pressure over the southeast states will be gone as the high pressure to our south or nearly overhead builds north of Central Florida placing most of the South and Central Florida in a SSE-SE to NNW-NW steering flow.  It's getting to be that time of year where we can start to include coastal morning showers into the equation. I've noticed that for several days the NAM and GFS have been implying showers along the east coast from Brevard and points south should have occurred, but this has yet to actually happen until this morning.  So we might be on a new trend here which will be worth watching.
 
Should this climatological aspect of the mid-late summer rain cycle indeed begin...these showers normally occur between the hours of 4am-9am into late September given favorable conditions exist for such to occur.

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Sunday, August 1, 2010

Today Could Be The Day We Get Needed Storms

NOW: Sea breeze has become established along the very immediate coast early this afternoon from Cape Canaveral south but has apparently made little inland progress. The latest KSC sounding just came in and depicts some form a west to east component at all levels of the atmosphere. Additionally, it is very moist with a PWAT above 2.20". Some showers and storms have formed west of Ocala and thunder is audible from the reporting station in Daytona with a shower actually moving off the coast into the Atlantic. Inland temperatures are climbing into the mid 90s. Radar trend is showing increasing shower and thunderstorm activity well off to the NNW-NW in North Central Florida. There is also some isolated activity near West Palm where it appears there has been a Lake Okeechobee-Sea Breeze collision already.

TODAY: Earlier this morning the sounding wasn't quite as 'hopeful' for the east coast of Brevard as far as rain prospects...so given this last and latest piece of info the trend has been favoring this area more for a shower or storm today...most likely the north half of the county. The atmosphere is juicy and upper level temps have dropped a degree or two at 700mb-500mb as one goes up. Also in our favor COULD be a boundary laid out due to outflow from yesterdays activity that was hefty and numerous across the state near Gainesville to Ocala. Can't find a boundary laid out specifically though...just a suspicion.

With the latest sounding information...and latest model runs...hard to come down to specifics, but can come up with a few assessments. That being...east coast sea breeze and slightly cooler air aloft combined with a juicy air mass with plentiful heating inland could boost the thunderstorm coverage activity and intensity this afternoon in the 'plentiful' category across the N. 1/3 of the state...the southern extent being from near KSC west to Orlando-Tampa Bay. Current activity to the north seems to be drifting toward the SE slowly along the eastern fringe of high pressure centered near East Central Texas.

In brief, best chances for the immediate coast to get a storm today...particularly from Melbourne Beach north...and more likely from Oak Hill north. Titusville (which is not on the ocean though) appears to be in the cahoots for a storm given the current steering flow and liklihood of the sea breeze not penetrating much further west of I-95 up that way.

MONDAY: At time, looks like Monday could be back to conditions similar to Saturday but with more moisture throughout the atmosphere. If that is the case, then inland locations from Okeechobee along the spine of the state and through Orlando metro would again be most favored (as is typical)....give or take 30-40 miles either side of that line. Also, the east coast sea breeze might be more active shortly after noon time as it begins to impinge on the inland intracoastal. Storm motion will start to trend for southerly toward the WSW-SW late in the day.

TUESDAY-THURSDAY: Probably dry east of US1 or I95 as a more Easterly and somewhat drier component steering current becomes established. Back to Tampa to Ft Myers for the big late afternoon storms.

TOWARD THE WEEKEND: All eyes on the Tropics which by this might be tropical storm Colin (at least). We'll be hearing a lot about this yet to develop system in coming days...but current forecast tracks are very interesting concerning Florida interests at this time.

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Saturday, July 31, 2010

Widespread Heat, Isolated Storms Late

(Image from the Regional Climate Center and Florida Today newspaper and shows the driest region in the state for the past two months)
Very little change today from yesterday's chain of events as mid-upper level ridge axis persists across Central-North portions of the state and along the Straits at the surface. Warm mid-upper level temperatures continue. All in all, very little in steering currents in a somewhat overall stagnant and moderately moist overall air mass.

It's worth mentioning at this point that parts of Brevard, Osceola, and Orange County are the driest in the state this year for the June/July period (as noted in the graphic). This has also been a warmer than normal July for nearly all of the state and many parts of country as well. The trend continues in closing out the month.

TODAY: Much like yesterday, the sea breeze will be a little late in manifesting along the eastern shoreline, but not as late as yesterday. Melbourne set a record 100 degree high temperature Friday breaking the previous 97F reading set for the date 23 years ago. PAFB reached 97 and KSC got to 99. My porch in Cape Canaveral read 98 (very unofficial). Don't think the immediate coast will get quite as hot today assuming the sea breeze develops earlier...if even by only 45 minutes, but inland area temperatures will be comparable to yesterday. Accordingly, a heat advisory was issued for Seminole/Orange Counties. Expect temps along A1A to reach the 93-96 mark and 94-98 mark along US1 and points west.

Probably not enough moisture to support early afternoon activity along the developing sea-breeze, so we'll have to wait until at least the 3-4pm time frame for anything to form, which will likely be along and just west of I-95 anywhere from Oak Hill to Vero. Further south from Ft. Pierce - Ft Lauderdale could see something develop near the Lake closer to the course earlier.

Concern outside of the heat: The region from Oak Hill and points north toward Daytona- Jacksonville- Ocala-Gainesville (essentially the northern 1/3 of the state) could see some stronger storms today with associated wet microbursts...even closer to the coast, although they should remain isolated in nature.
Given the very light mid-level winds per the KSC morning sounding...storm motion will be almost nil..so whoever gets under a storm could get a good dousing with gusty winds and frequent lightning in or nearby any storms that can form. Again, the strongest storms will probably be the inland areas north of the Orlando area. Importantly, remember that lightning does strike outside of thunderstorms...so when it roars, stay indoors.

TOMORROW: Starting to look like Sunday will be similar to today...with the NAM being the odd ball out trying to bring rain to Eastern Brevard earlier in the day. It was implying the same yesterday for Sunday...so at least there's continuity for that model...but not buying into it.

MONDAY-THURSDAY: Pattern shift. Continued hot inland but not as hot on the coast with a definitive earlier sea breeze development. Continued low end rain chances area wide...limited to inland locales later in the afternoon into the evening. Probably dry through at least Thursday east of US1 all areas as a more definitive east to west steering flow develops...hope that changes.

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Friday, July 30, 2010

Warm to Hot Day Along the East Coast Early, Strong Storms Inland

SYNOPSIS: High pressure that stretched across the state from Atlantic to the Gulf  for many days made its final break yesterday with a western High pressure center in the Gulf retrograding further off toward the Texas Coast (and eventually the South Central U.S) and the eastern High center well east of the Florida peninsula. With those two highs taken care of we can now focus our attention on the low-mid level trough which extends down the Eastern U.S. seashore to near the Georgia Coast. The trough seems has dug just south enough to merge with a thermally induced trough (which will form this afternoon) down the spine of the state during max heating of the day. With the two high pressure centers well enough off either coast and a thermal trough in place...this puts Central Florida in a position of neutrality but with an overall SW flow at the lowest levels prior to sea breeze development, with the trough having the greatest influence of the three late this afternoon through at least Saturday. As such, believe the west and east coast sea breezes will not have much problem with working inland this afternoon.
 
TODAY: Showers and thunderstorms should develop along the East Coast sea breeze along I-95 by early afternoon as it works inland. Before that time, though, the coast will be quite warm to hot due to the delayed sea breeze onset this morning. Low to even mid 90 temperatures might be common, even right on the immediate coast. By late afternoon as we work into the early evening hours the lower portions of the mid-level trough may exert a stronger influence from Vero Beach north along the east coast and that fact combined with outflow from inland storms could project the closest activity to drift back toward coastal communities especially a bit inland along the I-95 to US1 corridor.  Overall storm coverage will be limited from what it might normally be this time of year due to warm 700mb temperatures at or just above 10+C degrees. The end result may be only a trace of rainfall right along the coast...but areas from Ormond Beach to Melbourne Beach may actually hear thunder (at least). Another favored area would be near Lake Okeechobee...although, like yesterday, this area is somewhat questionable.
 
SATURDAY: Much the same conditions and locations will be favored for thunderstorms as today, although the immediate coast might not even see a sprinkle. Just exactly how far east any storm gets is contingent on any one storm's strength (thus vertical extent) at the time, of which is impossible to know when or where that will occur today. Otherwise, it will be the same favorable inland locations.
 
SUNDAY-MONDAY: At this point these days are somewhat 'up for grabs'...but at this point the models seem to be hedging for at least Sunday and probably Monday to end up much like Saturday...but with time gradually favoring more of the west side of the state late each afternoon, particularly on Monday. However, early afternoon activity would still be possible on these days if atmospheric conditions warrant for the US1-I95 corridor all along Florida's East Central area.  Elsewhere, the big news story might be news of a big heat build up over the lower Mississippi Valley region which will spread west and north as we work into the beginning of next week.
 
TUESDAY-THURSDAY: Believe eyes will start to focus on the Tropical Atlantic as a wave or eventually perhaps a tropical depression approaches Puerto Rico by the end of the work week. Thunderstorm wise, activity will focus more toward the area of the state west of the Florida Turnpike.

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Thursday, July 29, 2010

Clash of the Sea Breezes

SYNOPSIS: High pressure that stretched across the state from Atlantic to the Gulf  for many days seems to making its final break today with a western High pressure center in the Gulf retrograding further off toward the WNW (and eventually the South Central U.S) and the eastern High center well east of the Florida peninsula. With those two highs taken care of we can now focus our attention on a low-mid level trough which extends down the Eastern U.S. seashore to near the Georgia Coast. The trough seems to in the process of a dig just south enough to merge with the thermally induced trough which will develop down the spine of the state during max heating of the day. With the two high pressure centers well enough off either coast and a thermal trough in place...this puts Central Florida in a position of neutrality, with the trough having the greatest influence of the three late this afternoon through at least Sunday. As such, believe the west and east coast sea breeze will not have much problem with working inland this afternoon.
 
TODAY: Upper level sounding from KSC was unrevealing as far as wind goes, and as would be expected given the current circumstances.  Moisture level (PWAT) was lower than yesterday but believe this will be only temporary as we work into the afternoon hours. Today could end up being a close to classic sea breeze collision day with activity beginning along and ahead of each as they work inland ...with the final amassing of the forces occurring over Lake - western half of Volusia Counties to the north southward to the North Shore of the Lake. In other words, just about anywhere west of I-95 and along and east of Route 27 in all of Central Florida.
 
By late afternoon as we work into the early evening hours the lower portions of the mid-level trough may exert a stronger influence from Vero Beach north along the east coast which would project the closest activity to drift toward coastal communities. The end result may be only a trace of rainfall right along the coast...but areas from Port Canaveral north toward Ormond Beach may actually here thunder (at least). Another favored area would be near  Lake Okeechobee...although the area is somewhat questionable at this time.
 
FRIDAY-SATURDAY: Much the same conditions and locations will be favored for thunderstorms as today, but with yet a better chance of more and stronger activity penetrating east of I-95 toward the coast. Just exactly how far east any storm gets is contingent on any one storm's strength (thus vertical extent) at the time, of which is impossible to know when or where that will occur today. But overall, these two days appear to be the best opportunity that the East Coast of Florida from Ormond south to West Palm has seen all summer for a thunderstorm.
 
SUNDAY-MONDAY: At this point these days are somewhat 'up for grabs'...but at this point the models seem to be hedging for at least Sunday and probably Monday to end up much like today...but with time gradually favoring more of the west side of the state late each afternoon, particularly on Monday. However, early afternoon activity would still be possible on these days if atmospheric conditions warrant for the US1-I95 corridor all along Florida's East Central area.  Elsewhere, the big news story might be news of a big heat build up over the lower Mississippi Valley region which will spread west and north as we work into the beginning of next week.
 
TUESDAY-THURSDAY: Believe eyes will start to focus either on the Tropical Atlantic of maybe even WELL OFF the Carolina coast as the mid level trough will be loitering well off the U.S. coast for several days and a wave approaches Puerto Rico. Thunderstorm wise, activity will focus more toward the area of the state west of the Florida Turnpike.

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Monday, July 26, 2010

Minor Update For Florida East Coast Readers

As we've worked into the afternoon hours it has become apparent that the East Coast sea breeze is making very, VERY little progress inland this afternoon. Apparently due to the fact that the mid-level ridge axis has shifted further south toward Palm Beach County abetted by a midlevel trough axis extending south from the New England through Mid-Atlantic coast.The cloud line that had nearly diminished is not reforming with daytime heating and actually being  weakly pushed  back to the shore line as cloud tops reach greater height.
 
Forecast models show winds just above the sea breeze boundary through 10,000ft to remain SW-WSW through the remainder of the daylight hours.
Moisture at this layer is ample enough to just sustain cloud formation and enhancement...and as such moderate cumulus are translating to narrow towering cumulus and rain showers. With additional daytime heating and subsequent destabilization some pockets of moisture (assuming they do not dry up) could coalesce to central points generating a hefty enough area for "just maybe" a thunderstorm. Coastal communities from just south of Ft Pierce to Daytona Beach are all in the penetrable zone for any activity that can actually get going.
 
The other possibility is that a decent enough storm could get going along I-95 which would send a cooling outflow back to the coast with an accompanying gust front looking cloud formation followed by little to no precipitation accompanying it.
 
My personal rain chance just went from 0-15.775% for the aforementioned area.

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Bonnie Not Enough To Recycle July's Weather Pattern

TODAY: Despite a slight increase in overall moisture, it's not all in the right places.  Early morning land breeze and synoptic analysis over the SE U.S. and Western Atlantic coupled with surface data indicate the low level ridge axis is along a Sebastian to south of Kissimmee line..and just about directly over head aloft over all of Central Florida.  This permitted the land breeze to from overnight..and such will occur each morning for the remainder of the week. A decent field of moderate cumulus formed with morning heat, but is quickly shifting inland as the sea breeze sets in. Despite the favorable low level flow and ample moisture for cloud formation here, the rest of the atmosphere remains unfavorable for shower/storm formation. Thus, the result as we work into the afternoon remains status quo of recent days.
 
Most favored area for very isolated activity today will be where moisture convergence is maximized along collisions of east/west coast breezes with lake breezes well inland just about anywhere within the spine of the state.
 
IT'S BEEN DRY:
I wasn't going to post today but might as well  recap the rainfall situation for the month for Brevard County...to specifically point out
the possibility that the region from S. Cocoa-Rockledge- Satellite Beach-Indian Harbor might be suffering the worst of an already bad
low rainfall situation.
The Titusville area might barely in the red if at all, as that's where everything has happened this month so far...there and extreme SW Brevard
west of Palm Bay. The lone one out in this specified area would be PAFB and Cape Canaveral, where each has
had a very tiny rainfall 'event' on separate occasions.

I was even considering writing the NWS MLB to see if someone  would provide
the low down on how this month has fared compared to past July's.
Wouldn't you know it, there's an article in the paper today summing it up!
What a coincidence. If you didn't see it, MLB is having the second driest
July for their reporting location on record. The other being in 1955...but
the total precip. for both July's is within the 0.80"-0.90" range which is
close to negligible, whereas Cape Canaveral has received 2.03" , at least in my backyard.
 
ELSEWHERE: Seems the most likely area today for rainfall will be just inland of Ft. Myers northward anywhere over the west half of the state.
Hard to decipher a 'best possibility' locale at time of writing. There already has been a shower on Tampa Bay this morning though.
 
SO WHEN'S THE CHANGE FAVORING EAST COAST RAINS COMING?: Will elaborate more on this tomorrow. Just need to monitor model outputs for another 24 hours for continuity and agreement among them. For a heads up though, there could be trend favoring the east coast for afternoon and early evening activity by late Thursday-Saturday (and maybe Sunday). At this time there are factors favoring this regime, but there is almost an equal number of factors precluding things to unfold as such. Either way, the chance looks just above meager at best for now, which is better than we currently stand.

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Sunday, July 25, 2010

Likely Dry With Uncomfortable High Heat Indices Inland

The sky is crystal clear blue other than a small cumulus patch over the seemingly often favored Cape area just to the north about 5 miles away. That area can squeeze water out of a rock.
 
Monitoring a batch of moisture that came off the extreme NW Bahamas during the late morning hours though 'just in case'. There is some shower activity associated with it as I type. That area is just enough to keep the ears and eyes perked, but probably more a tease than anything else.
 
Upstream sounding from Miami was almost just as dry as us even though water vapor shows them in some mid-upper level moisture just recently. So maybe their sounding is unrepresentative of the conditions down there now. The same water vapor image shows us dead center in the driest of air.
There's going to have to be some mighty powerful late afternoon/early evening magic to get anything going further south later today and even at that the mid-upper level temps will likely remain too warm for anything closely remote to robust.
 
Therefore, most of East Central Florida looks to remain dry and nearly cloud free most of the day with very warm temperatures along the coast to down right hot further inland. Lows end remote chance of a storm away from the coast from Orlando and points south as we work toward sunset. Lows near 80 and highs at or just above 90. Warmer inland. 
 
If one wants to see lightning and hear thunder today, head to the Keys and up the west coast toward Tampa. Or the Panhandle.
 
INTO THE WEEK: Refer to yesterday's post. No significant change from that line of thinking yet. At least, not significant enough that it's worth mentioning.

 

 

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Saturday, July 24, 2010

Lots of Features But Little Action

(Image: Water vapor image shows TUTTs near the SE Texas coast and Eastern Cuba, remnant TD Bonnie approaching Louisiana's Big Toe)
SYNOPTIC RECAP: The TUTT that was first noted last week north of Bermuda continues it's epic round the clock journey which took it eventually across Florida, into the Central Gulf, and now about to 'landfall' on the southeast Texas Coast. Another TUTT moving along at a good clip was north of Puerto Rico yesterday and is now generally located just NNE of the eastern tip of Cuba and moving WNW. Minimal Depression Bonnie on a downward spiral is approaching the Louisiana coast, circulation seemingly to continue on pure momentum with no punch. High pressure located over the SE quadrant and centered near the Carolinas is also displayed with moisture riding along its crest over the Great Lakes and NE U.S...round the clock well into the Atlantic..with a new leading edge just now imposing on the southern east half of Florida from the east toward a westerly direction.

LOCALLY: Conditions across much of the state are fairly uniform. PWAT is generally just above 2.00" everywhere with a SSE-SE flow from the surface upward throughout the steering column. No triggers are evident to get the show rolling though. Early morning near shore convective showers were widely scattered all along the entire Florida east coast, mainly along and east of I-95 but are waning as we head toward noon.

TODAY: Believe a more deliberate east coast sea breeze will be established shortly after noon which would put a halt to land falling Atlantic showers, except south of West Palm to South Miami. West Coast sea breeze will have a hard time establishing today so folks anywhere west of Orlando will feel the heat, just like before Bonnie moved in (high end mid-90s in many reporting locales). Coolest air will be found east of US 1. Believe that surface winds will be light enough inland though for formation of lake breezes which will be the triggering mechanism necessary to escalate the convective processes necessary for generation of intensifying rain showers into a sparse population of thunderstorms, mainly around the tip of Florida south of Lake Okeechobee then northward along Route 27 and all of those counties toward Tampa to as far east as maybe west portions of Osceola County, Orange County, and all of Lake County later in the afternoon.
It's almost easier to figure the least likely area to get a thunderstorm today, that being all but extreme SW Brevard County, Eastern Indian River and St. Lucie County..and perhaps extreme Eastern Volusia. All precipitation off the radar scope by 8:30pm.
TOMORROW: The TUTT referred to in the opening paragraph seems to be on a motion trend that would take it just along the Florida Straits tommorrow. There will be a period during it's approach that rain chances will be close to "Absolute 0" over a vast expanse of the state, but that will probably be sometime overnight while everyone is asleep.
By Sunday afternoon things aloft will be in a state of "Wind Direction Chaos" with conflicts between the low-mid-upper level direction (not speed) due to passing of the TUTT and attempting re-establishment of our old "Atlantic and now also SE US High Pressure" nemesis...but when push comes to shove tomorrow could end up much like today as we work into the early afternoon time frame..with stress on the word "could". This will require refinement once upper level data is monitored during today and early tomorrow so that a trend can be established.
MONDAY: Transition day toward "Dry Weather Takeover" - less activity everywhere as some drying begins.

TUESDAY-WEDNESDAY: High pressure surface and aloft. Lowering PWATS and diurnal land/sea breeze wind pattern and inland lake breezes. Extremely isolated inland afternoon thunderstorms by day generated by the interaction of the aforementioned breezes. Clear at night.

THURSDAY-NEXT WEEKEND: Way out there. But there are hints that the high pressure ridge across the state will either weaken and split down the middle (over Florida) with the west half retrograding toward Louisiana, or the entire axis will flat out sink south toward the keys. Either way, a trough of low pressure which will be present along the the U.S. East Coast as far south as North Georgia could dampen the spirits of nemesis high and put Florida's East Half in a formidable SW steering current with higher precipitable water values (PWAT) present. This could mean some showers and thunder storms closer to those living anywhere in the eastern half of the state.

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