"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".

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 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 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 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 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.
I wasn't going to post today but might as well  recap the rainfall situation for the month for Brevard 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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Friday, July 23, 2010

Is Bonnie A Sheep in A Wolves' Clothing?

(Image: Water Vapor imagery showing convection associated with Bonnie and the upper level low in the Gulf)
Might as well bite the bullet and use the opportunity presented through having a blog to post some unconventional thinking this morning. Please note that anything written here is likely to totally NOT agree with most everything being posted through OFFICIAL CHANNELS. I guess if I'm going to be totally wrong, I might as well do THAT right.

As of 10am 'Bonnie' (as it has been dubbed) is moving in on Miami at a steady pace. Upon looking at the Miami radar it is hard to locate a completely closed circulation...there seems to be a break in the circulation around the southern periphery, but that's neither here nor there. Concerning the weather here locally.

NOW: As can be seen by the included image the main impact as far as precipitation goes from the system (as it stands now, only) has moved onshore. This is a water vapor image. What can also be seen is that East Central Florida lies on the cusp of where the deeper moisture comes to an abrupt halt. It already appears that drier air is impinging. Also note the beast in the Gulf. That is the upper low that crossed the state yesterday. That low combined with the nemesis high pressure over the Atlantic is tearing at Bonnie's integrity at every given opportunity. Numerous low topped rain showers populate the near shore waters well off shore of Southern Volusia County and points south and are evaporating as they approach the coast up this way in Canaveral but look like that will reach the coast of South Brevard shortly.

TODAY: Believe most forecasts are erring on the side of caution. Totally understandable. Other than that, not much to say that wasn't alluded to yesterday. North Brevard will remain on the cusp..but feel this cusp will shift further south with time during most of the day leaving only the more susceptible area from Indian River County and points south open to accumulative rainfall amounts. Things could change locally by late afternoon once the system has actually crossed the state...but I'm just now beginning to lean toward discarding even that notion as I write. I am thinking that the worst of 'whatever it will be' will be arriving from Sebastian to West Palm in the mid-late afternoon hours in the form of gusty pressure gradient winds with higher gust embedded within the bigger showers. Locally, rain showers could be impacting parts of Brevard by the time this is read by you though, but significant accumulations appear to be unlikely. These showers will be small and move along at a very brisk pace.

TONIGHT: Show's over. Maybe some sparse showers along the immediate coast at any time.

TOMORROW-MONDAY: Perhaps some trailing moisture will continue to be drawn toward the system and across the state..the higher a latitude the 'system' attains the further north will be the moisture feed. Coastal rain showers by night and early day transitioning inland as the days progress. Maybe even thunderstorms further inland...that's questionable.

LATE MONDAY INTO TUESDAY: Could easily transition back to dry until proven innocent. Nemesis high will be back for round two. The real mind blower is that Bonnie might never even make it beyond the central Gulf as anything more than a depression. Just something to ponder at this point though. I don't even totally believe that one yet. At least the folks in the Oil Spill Region would be happy.

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Thursday, July 22, 2010

Will The Circus Come To Town?

(Image: Enhanced infrared satellite imagery shows a narrow swath of high clouds approaching East Central Florida in association with an upper level low)

SYNOPSIS: Strong surface high pressure in the near term remains the playing card for today's weather. Aloft an upper level low is located near the SE Florida Coast which is moving WSW. A narrow swath of high clouds passed over Brevard County around 9am and has already cleared the immediate area as of 10:30am. Meanwhile, a tropical wave is still evident on surface observations and satellite imagery near the NE tip of Cuba extending toward the SE Bahamas.

TODAY: Dry and very warm to hot, but not as hazy as yesterday. With that said we can go straight to the next topic on the agenda which is the Invest 97-L area. At 11am the Hurricane Center will proclaim this region to be either a Tropical Depression or Storm Bonnie. My impression is that it should be tropical depression 3...we'll see.

TONIGHT/EARLY TOMORROW: No matter what the storm status will be at 11am..any strengthening to occur will be hard-pressed to occur for two reasons. It will not only be competing with wind shear from the aforementioned upper low but also with the unaccommodating landscape of Eastern Cuba. Any circulation now detectable by the first rounds of visible satellite imagery of the day shows the circulation to be hugging the Cuban coastline. During the course of the evening the circulation will follow along the coastline or maybe even flat out over the landmass.

Locally, expect that sometime after midnight the first showers will be approaching the extreme SE Coast of Florida and the Upper Keys. Higher clouds will begin to extend as far north as Volusia County by day break with the chance of rain not far behind. By daybreak the showers could be reaching the Sebastian Inlet area and by noon time be as far north as Central Brevard.

TOMORROW AFTERNOON-EVENING: This is the time frame that it currently appears the worst will occur (under the assumption this systems maintains a WNW track). It should be pointed out that it is quite possible that although the center of activity will be much further south (of Brevard) the strongest wind could actually occur along the coast of Brevard and Indian River County due to the pressure gradient rather than the actual circulation close to any sort of central point further south near the lowest barometric pressures.

As far as rain is concerned it's going to be an all or nothing situation with a very fine line as to where the northern extent of the rain possibilities will exist. Again, based on a current line of assumptions, the cutting off point will be Southern Volusia County. If we put the rain and wind chances together the resultant summation would be intermittent rain showers coming in off the Atlantic which could contain some pretty good wind gusts in the vicinity of each one...outside of the showers the wind would be a steady state around 18-25mph.

SPECIAL NOTE: It cannot be stressed enough that any deviation to the north or south of the projected track (of the depression?) will highly impact how, who, and where active weather will occur. Therefore, any interests should remain abreast of the latest local weather through outlets provided by the National Weather Service.
OVERNIGHT FRIDAY - SATURDAY: The show's over. Moisture will be dog tailing behind the system rain chances will be better than these past few days or pretty much close to what one would normally expect this time of year for afternoon shower/thunderstorm activity favoring the area west of I95.

BEYOND SATURDAY: Normal to just below normal chances of thunderstorms and not quite as hot. Most activity favoring pretty much any where west of I-95. Moisture levels might be enhanced for a brief period, particularly over the west half of the state due to another tropical entity of unnamed nature.

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Wednesday, July 21, 2010


(Images: Morning KSC Sounding shows very dry air aloft and a sample of various directions that a yet to develop tropical low could take. If viewing this in Facebook click on link to see both images.)

Short post today. Stacked high pressure over the Western Atlantic across the Central and Northern Florida peninsula remains firmly entrenched. KSC sounding is showing a PWAT of 1.18" which is possibly less than 10% of normal. That speaks for itself in the short term (today). Conditions to persist through tomorrow as well.

The tropical area of interest between Hispaniola and Puerto Rico is doing nothing other than moving toward the WNW @ 10mph...and this trend will continue. The National Hurricane Center has called off an earlier scheduled fly by of this area for the day to boot.

Included in this post is a sample of the direction that this area could take if it develops a closed circulation. If anything in this graphic causes confusion ignore the entire product. It is not for planning purposes. Believe this area will develop a closed circulation but just exactly where it does so might be a surprise to all. Thus, until when or if this does occur further discussion would be pure speculation. At this time I see no reason why any significant organization would occur, at least not for the next 24 hours.

About the only thing that might be worth mentioning is that assuming the system does not wash out it COULD bring enough moisture and instability to the area by over night Thursday into Friday to consider upping our chance of rain showers significantly. I'm not entirely ready to totally bite on even that notion though. Tomorrow is another day until then...

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Tuesday, July 20, 2010

Seize The Moment

Current and Today: Latest satellite/radar imagery and animations, surface / sounding data, and short term forecast models all spread the same good news regarding precipitation for today. None. Not for East Central Florida that is. Barely a cloud in fact. But it will be hot everywhere except within 5-10 miles of the east coast shoreline. The SW and West Central Florida Coast will bear the brunt. But it's not the warm/hot weather that's making weather headlines last I tuned in. It's all eyes on the tropics.

SYNOPSIS: Strong high pressure from the Western Atlantic and across North Florida reigns the roost. There are no discernible perturbations or pockets of moisture or any other atmospheric creatures lurking in the shadows that will impact Central Florida through Wednesday. On the other hand, there is a tropical trouble maker out there in the form of an active tropical wave located near Puerto Rico that's been the topic of discussion. Implications of the impacts this system might have for Central and South Florida, as well as what type of weather will exist after it's passage (in whatever form that will eventually be) are both worthy of mention.

TODAY-EARLY THURSDAY: Clear to partly cloudy skies with warm evenings and hot days. Somewhere in there a pocket of moisture could ripple through with little impact. From an alternate perspective, there's about a 95% likelihood that it will not rain north of Sebastian Inlet. Head toward Miami and one's chances of a fast moving, brief shower go up but even those are few and far between. The area near Puerto Rico will waiver (excuse the pun) somewhere between being an open wave to closed circulation for another 18-36 hours as it pushes WNW toward extreme SE Florida. Wind shear on the north side and proximity to land being the primary reasons for the less than eager assemblage of the required forces.

MID-DAY THURSDAY - SATURDAY: Rather than muddy the waters and confuse things by elaborating on what/how/or why the various models depict what they do...I'm going to leave it at that conditions as we now know them will deteriorate as cloud coverage and rain chances go up. South Florida and the Upper Keys come first...then up the coast and into the Lower Keys as time goes on. We can elaborate progressively more on this system with each upcoming post.

One tid-bit of wisdom. Word will surely run rampant through all forms of media about the tropical developments, but trust only those sources known for reliability. Word of mouth about the tropics is no different than any rumor. As it spreads the truth progressively gets further from the truth. So consider your source.

AFTER SATURDAY: This system will not be the end all. There could be yet another wave following on the first one's heels which would continue the moisture rush...or another scenario is that the first one will abet in cracking the High Pressure's noggin once and for all as it merges with a mid-latitudinal trough which will have formulated along the U.S. East Coast.

Maybe this system in the long run is the long needed blessing in disguise rather than the wolf in sheep's clothing. The beginning of the end. An ends to a means. Maybe, just maybe, the thunderstorm season will finally begin and rainfall amounts over Central Florida will return to normal (from their below normal levels experienced so far this summer). On a side note, the folks from Ft. Lauderdale and through the Keys have climatologically had their share of measurable precipitation this summer...wouldn't you know that same area is the one most likely to be affected by the upcoming tropical event. Stay Tuned!

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Monday, July 19, 2010

It's In the Details

(Image: Last vestiges of the only blip on the radar within 100 miles near the tip of the Kennedy Space Center Cape at 10am this Monday morning)
In the broad scheme of things nothing has changed from past days, but as expected could happen, there is currently a minor, unforecasted and probably only temporary change in local conditions which will affect many areas at different times today across Central Florida.

NOW: The latest KSC sounding was released and the verdict is in. The 700mb temperature has dropped about 2 degrees C and moisture (PWAT) has increased to nearly 2". Pretty significant. Additionally, some weak PVA (positive vorticity advection) is occurring overhead. As a result, some blips on the radar screen have popped up around Cape Canaveral the past hour and there was some increase in low level cumulus clouds along the coast. The Tampa sounding also showed in increase in moisture. It should be noted that none of the models indicated this unfolding of events would occur until about the latest RUC run which just came out. Better late than never I guess. Even still, the NAM did not pick up on it, just to show how small scale this is.

TODAY: There appears to be an axis of increased moisture stretching from near Sarasota to just off the coast of the Cape. LDIS plots show this nicely. Believe this swath first made its presence none very early this morning as showers moved onshore near West Palm Beach well before sunrise. Since that time that 'disturbance', if you will, has moved north and is now stretched across the entire Central Peninsula. Along this moisture axis is some PVA as well. Just how long these conditions will remain locally is the clincher for the forecast. Believe that by early-mid afternoon these conditions will move on or simply dissipate and we will be back to status quo along the immediate coast. But before that time some land falling rain showers could occur from Sebastian to Daytona but mostly likely from Melbourne Beach to Oak Hill. Not expecting thunder though.

MID-LATE AFTERNOON: The coast of East Central Florida will probably clear of rain chances, but the inland areas west of the spine of the state as well as from roughly West Palm to Miami further south will maintain some precipitation chance integrity through the day's remainder. The best chance for thunderstorms will be along the immediate West Coast where any sea breeze that can develop will remain very close to the coast. Tampa Bay preferred.

TUESDAY THRU FRIDAY: The general pattern of dry weather will continue across East Central Florida, although the possibility of another 'event' such as what is currently occurring overhead is not entirely out of the realm of possibilities. Hence, daily if not hourly vigilance (for the 'super weather minded') will be the rule. Temperature wise -- Low around 80 and high near 90 (slightly warmer inland) throughout the period.

THIS COMING WEEKEND: A tropical wave roughly in the vicinity of Puerto Rico is forecast to approach South Florida on Saturday. Two consecutive runs of the NAM have tightened the disturbance up to nearly a low grade tropical depression, whereas the GFS only recognizes it in the future to remain a mere perturbation (wave). Believe the NAM is overdone for a variety of reasons, but it will be interesting to see which model was correct as we enter the late Wednesday time frame to see how things have progressed (or not progressed).

Either way, this area of interests poses the first real possibility of change in the broad picture which has existed over this area for a while now. Other than this area, there are no tremendous changes forthcoming. Our weather from late Wednesday - Friday will be highly contingent upon what type of organization, if any, the area acquires. Odd as it may seem, the better it gets organized the lower the rain chances go until it actually reaches the state. At worst, rain chances could increase to around 40-50 percent...with higher chances the further south one goes. And on the other end of the spectrum there will be no change from what we've already been experiencing. If I had to hedge my bets though, I'd go for the gold and say we'll see that increase in rain chances...especially on Saturday.

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Sunday, July 18, 2010

Break the Grip of the Rip

(Image shows the procedure to escape a rip current)
RIP CURRENTS: I used to hear it called 'undertow' but not in quite a while. Perhaps it's because such terminology is misleading. A rip current is a horizontal current. It doesn't pull people under - it pulls them out. Be advised that over 67 rip current rescues have been made the past couple days in Brevard County alone and the conditions persist for them them to continue. This is an especially plausible concern considering the weather conditions lately that lead people to the beach. The best way to avoid them in the first place is to closely observe the ocean's surface close to shore. They are often discernible by a particularly odd, choppier appearance to the water's surface than surrounding waters. But this may not always be the case. Avoid venturing into waters above your waist.

SYNOPSIS: Persistence. The key player, as had been the case now for a couple of days, is strong "Bermuda High" pressure anchored across the West Atlantic ocean with the axis extending west across roughly the Florida / Georgia border . Indeed, latest KSC sounding indicates an even warmer 700mb layer than the past couple of days at 12+ C degrees which will greatly inhibit development of even a weak rain shower. In the area less directly affected by this high pressure system (which includes extreme South Florida, Cuba, and the southern Bahamian islands) minor perturbations or weak, inverted troughs of low pressure are rotating around the southern periphery providing for passing blows of enhanced atmospheric moisture and subsequent rain showers and even some thunderstorms. In fact, Puerto Rico experienced a land-falling waterspout yesterday which caused damage and disrupted activities for the Caribbean Games. Saharan Air Layer (SAL) conditions appear to have abated for the short term locally - the sky looks quite blue this morning.

TODAY: One of those passing blows crossed South Florida last night and early this morning and provided for some passing showers from around Ft. Pierce to Miami. Some residual moisture resides down that way this morning...just how long it will last is questionable. Model guidance suggests it will be enough for more activity down there today, but I believe it is overdone. In any case, closer to home for Indian River and Brevard County the forecast remains dry. Low temperatures near 80 and highs near 90 have been the rule the past 2 days and this trend will continue throughout the coming week. Thunderstorm activity will be restricted to western portions of Lake Okeechobee and points west of there.

MONDAY: Perhaps some increased moisture will make its presence known. I'm playing the pessimist today and leaning toward last night's NAM solution which introduced no rain. Any of those passing blows will remain south of Brevard, but could eke out a shower along the Treasure Coast. The further south one goes the more likely one is to get into the 'juice' and rain showers.

TUESDAY-SATURDAY: No change. This period will be characterized by a pattern which was discussed several days ago and has now come to fruition. That being the predominant conditions will be rain free with only sparsely timed periods of enhanced moisture and a slight chance of showers which could happen any time of the day or night every 36-60 hours and last for about 6 hours when they do make an impact. Timing of when such conditions will approach and make an impact is impossible to predict more than 24 hours out.

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Saturday, July 17, 2010

"WeatherFree" Day

(Image: Morning sounding paints a thousand words)

Short one today. No change from yesterday with less rain chance all locations.
Upper level impulse over the western Bahamas might reach east half of Brevard County during the day..but the only impact will be an increase in high level clouds if it can even make it here. Otherwise, little chance of a rainshower or storm today anywhere in Central Florida, but if were to occur it will be somewhere along route 27 west of Orlando.

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Friday, July 16, 2010

Earlier Coastal Rain Chance - Later Well Inland

SYNOPSIS: Two dominating features on the map this morning. The biggest player is strong high pressure both at the surface and aloft centered over the Atlantic, the ridge of which is primarily located East-West across N. Florida. The second feature is a TUTT low approaching extreme SE Florida. At the surface an inverted trough most pronounceable extends from Central Cuba northward toward the Ft. Lauderdale-West Palm Beach area...paralleling the coast up to Brevard...then arcing NE off the coast from the Cape and into the Atlantic.

TODAY: The aforementioned inverted trough will be passing through during the pre-noon hours and damping out as it does so. Surface moisture flux divergent values are noted very negative all along the coast where the trough is located, and thus fairly fast moving scrappy cumulus are noted in Canaveral at this time. Morning sounding came in less than impressive in the moisture category above 5000 feet- i.e., most of it is trapped below 850mb (and hence the scrappy clouds). Within the drier air aloft resides a 10+ C degrees 700mb level temperature. SAL (dusty/dry) mid-upper level air resides there. Radar is rain free.

All things now having been said and done, despite the presence of strong divergent values noted and low level moisture...I'm tempted to include very samll rain chances right along all of the Florida East Coast...but believe that possibility will reside either far south from West Palm south closer to the TUTT low where greater moisture and covergence resides, and further North for Volusia and Flagler Counties where the affects of the SAL are less pronounced. It's Brevard and Indian River that will have the least chance of coastal rain showers. One thing worth noting though is that regardless of where the showers are...wind gusts could be quite hefty within those that do occur (even if they are not thunderstorms!). Reasoning behind why that is the case will be reserved for a later discussion, since the opportunities for such conditions to exist again will occur many more times through September.

Best chance of storms today for Florida in general will be around the southern tip of the state and up the west half, particularly mid-late afternoon over parts of Hillsborough/Hernando/Western Polk/Western Lake Counties which will continue into the early evening. The immediate coast of Central Florida will likely experience no rain whatsoever after 1pm.

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Thursday, July 15, 2010

"Back in the Saddle-Point" Today

(Image: Latest image courtesy of the NWS and LDIS shows a pond of low lapse rates / Theta-E in the mid levels over Brevard)
RECAP: Rain activity materialized yesterday as forecast both in timing and locations was later in the day that the coverage of shower/storm activity was a total "fail". There was a strong storm or two far away...but they were very few and far between. The only cause I could come up with as to why this occurred was the warm mid-level temperature of 10C at 700mb.

SYNOPSIS: As was the case yesterday, this morning most of East Central Florida remains between high pressure to the east and high pressure to the west. Additionally, we have a tropical inverted low pressure trough passing to the south with another trough digging down the U.S. east coast which ends to the north. In other words, we are positioned in East Central Florida in what is known in meteorology as a col, or neutral position (the saddle point)... we're neither here nor there.

LOCAL ANALYSIS: The included image shows an area of very low 950-700mb Theta-E over Brevard County. Such an area was over North Central Florida yesterday which I believed would greatly inhibit rainfall chances for at least the first half of the day for that area (which indeed was the case). The area isn't quite as strong though today, but it is over this area now. Otherwise, morning rawinsonde data shows a continued moist air mass with a PWAT at 1.97 inches -- just a neglible tick lower than yesterday. This is definitely ample moisture for shower/storm generation. 700mb temperatures remain nearly constant from yesterday at +10C though, but 500mb temperatures have dropped about 2-3 degrees. A light easterly wind component is becoming apparent just above the surface all the way up.

TODAY: Partly cloudy to occasionally cloudy to start the day. Early sea breeze and no rain along the immediate coast, but some widely scattered showers are possible between the US-1 to I-95 corridor between 11am - 1pm anywhere from Vero-Daytona. High pressure from the east will eventually build in during the course of the day exerting a SSE toward the NNW push of any activity that does happen to form to the inland counties west of Brevard and Indian River County. Further south little if any activity is expected. The most sincere efforts will be made for storm generation inland where Lake Breezes meet the East Coast sea breeze. Activity could be more widespread and stronger today due to the cooler than yesterday temperatures cited at 500mb. Do not believe the west coast sea breeze will have much of an influence except well west and north of Orlando
TOMORROW THRU MONDAY: Timing of rainfall nearly impossible to predict with a reasonable amount of accuracy. Suffice it say that we will be placed right along the western periphery of the Atlantic high pressure system for quite some time (well into next week). This will make the East Central peninsula open to both totally dry lapses as well as potentially wet periods lasting anywhere from 6 hours to 2 days contingent upon what comes out of the the tropical Atlantic.

For instance...currently, a TUTT low is approaching the eastern Bahamas with a tremendous amount of mid-upper level atmospheric subsidence and a dry Saharan Air Layer (SAL) air slot wrapping around its west side. The dry, dusty air already impinging on the Bahamian Chain is clearly evident on satellite imagery time lapse, so it's not that far away. The jury is out as to whether this area will actually reach our coast during the next 24 hours. If it does that would mean no rain for that time frame until the TUTT passes on...which would take about 18 hours. Latest animation suggests that the 'severely' dry area is thinning though and slowing in forward progression as the TUTT heads this way. Beyond this feature, there are no other immediate items of note looming on the horizon, and I don't anticipate there will be any for a few days.

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Wednesday, July 14, 2010

Could Be a Great Day for Sky-Pix

(Image: A Sky-Pic of towering cumulus rapidly becoming a storm yesterday looking toward Merritt Island )

RECAP: Events unfolded yesterday pretty much as expected for the earlier portion of the day, although coverage of storms was lower than expected. The main shows in town were completely over N. Merritt Island and down by Vero (for which a 'possible funnel statement' was issued). It was later in the day that events unfolded in a fashion somewhat unforeseen. In other words, there wasn't a solid sea breeze collision between the west and east coast except for in a very ubiquitous fashion near sunset...instead of colliding they met, kissed, and died with the setting sun. Very low theta-E / lapse rates indeed shutdown the region to our north as was feared would occur...and the west coast sea breeze swept completely across that same region as well in short order with no convective results.

SYNOPSIS: High pressure is centered about 100 miles west of the Keys in the Gulf and another center is well out in the Atlantic. An inverted short-wave trough is moving through the Bahamas and approaching the extreme southeast Florida coast around the southern periphery of the Atlantic high. Although models depict these two pressure systems 'joined at the hip' by an axis running directly overhead I do not believe this is the case at all. In actuality, the peninsula lies in a no-man's land between the outer fringes of each of them with very slight surface troughiness that will be running down the spine of the state once daytime heating begins (thermally induced trough). Meanwhile, the latest KSC sounding shows a very moist atmosphere (PWAT of 1.99") with winds of 8 knts or less up to 20,000 ft).

TODAY: Much like yesterday to start...but sooner. The wind is essentially calm all up and down the coast this morning..and took all night and most of the pre-sun rise hours to achieve that status...and sincere land breeze is not evident. Thus, the sea breeze circulation process will not take as long to get its wheels turning later this morning.

TODAY (EARLY): Expect the sea breeze to begin between 10:00am - 11am. The further south toward West Palm the sooner it will be. Watch the sky for large cumulus clouds to form anywhere from extreme southeast Florida north to the port (Canaveral) within the hour of the sea breeze. Like yesterday, there is a very strong area of low 950-700mb Theta-E/lapse rates spread all across the N. Central Florida peninsula of which the Space Center is right on the southern cusp off. Thus, it is highly questionable as to whether they will have a show over the Wildlife Refuge as they did yesterday. Although there is the ever so remote chance of a funnel cloud or even a waterspout over the intercoastal, those chances at this specific time do not look quite as possible today as yesterday...but there is that low end's just even lower than yesterday.

EARLY-MID AFTERNOON: Activity, outflow, the sea breeze...(the whole kabosh) will drift toward the west and the coast will scour out with some debris cloud remnants lingering in the vicinity of where a shower/storm managed to form. There should be a lull in any activity during the mid afternoon before "West meets East meets Lake Breezes" somewhere along a North/South line running from Lake Okeechobee to just north of Orlando by the latter portion of mid afternoon. Additionally, a mid-level system will scoot across the north central peninsula (like around Ocala-Gainesville) where things will have been quiet..until that system passes over. At that time this region will also be open to convection (storms) which will be moving from west to east.
Storm motion from just north of Orlando to points south will be chaotic and totally contingent upon where outflow boundaries collide and resultant development propagates. Further north there should be a little bit of a definitive eastward push.

AFTER DARK: Activity to the south will quickly wane whereas the activity to the north could persist well into the evening as it pushes toward the east coast from Daytona northward. It's doubtful it will actually reach the immediate coast though when all is said and done.

TOMORROW AND DAYS OUT: In general, the ridge axis at all levels will reside across North Central Florida especially on Friday...but it is noted that there will be periods of widely variant behavior in its actions. I'll be watching just exactly what affect tropical waves or inverted troughs have on the Atlantic High pressure system each and every day...since what happens with the western extent of that system across the peninsula will have a large influence as to where these waves go...what type of moisture we'll have...etc ad naseum. In other words, we will have a number of days ahead with great variability between each and every day. Temperatures will run right at normal area wide.

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Tuesday, July 13, 2010

Light the Fuse...But Will it be a Dud?

REVIEW: Pretty quiet day yesterday overall in the broad scheme of things, considering how actively it began early around noon time. The only real storm in Central Florida was over N. Brevard which resulted from a collision of OFBs (outflow boundaries). If you weren't in or near Titusville it was dry other than some other sparsely scattered showers. A "fluke of nature" shower went up over Patrick AFB around 3am this morning abetted by the wake of yesterday's departing wave. But it was short lived, small, and evaporated into oblivion before the sun came up.

SYNOPSIS: No atmospheric 'surf' today (i.e., no waves/disturbances). The main weather influence for the immediate area today is high pressure extending almost perfectly along the northern coast of the Gulf of Mexico from Texas to Florida at the mid-levels. At the surface the axis of high pressure tilts south to a location over the tippy toes of South Florida. Clockwise circulation around the mid-upper level high is slopping high levels clouds over it's crest and around the bend, draping high level cirrus debris clouds across the area like wet clothes hanging on the clothes line.

Latest KSC sounding indicates ample PWAT (precipitable water) for showers/storms at all levels, but other than than very little to speak of especially with relatively warm temperatures aloft unconducive for initial shower formation to explode in and of itself. Winds are another story, namely because they are close to non-existent the whole way up to 35,000 ft! Storms in earnest won't manifest without the aid of surface boundary convergences (a.k.a. - sea breeze / lake breezes) which can't occur until we get some good heating and early shower activity collapses and sends out a boundary. I am very suspiciously eyeing an area of very poor (low) lapse rates loitering along the the west half of Central Florida which could be approaching the region as we speak. Also wondering if subsidence behind the parting wave will put the lid on possible early activity. If this area of low lapse rates and the subsidence theory is a reality......shower activity could be non-existent for earlier portions of the day for the coast. But playing the devil's advocate (i.e., favoring a rain chance)....

EARLY TODAY: Unlike the past few days, sea breeze initiation will be earlier...between 10:45am - noon. As such, coastal temperatures will be normal. If it's going to rain along A1A anywhere from West-Palm to Oak Hill it's going to have to be within 1-2 hours of that time frame. For any one up by Canaveral, you might want to eye the Cape extension area for something to go up over areas like the Merritt Island Wildlife Refuge to Pads A and B. Could a funnel or waterspout be possible with such light winds aloft? In any case, this is the area that it seems most likely to at least get some lightning from if it even initiates at all.

LATER TODAY: Regardless of whether or not the A1A-US1 corridor from Oak Hill-West Palm initiates it will be the perfect "west coast meets east coast sea breeze collision late in the day" type of day. Just where this collision will occur is any one's guess. We can take it a step further though and wonder just exactly where a storm(s) will go up once the collision occurs. Just because a Lake-Lake, Sea-Sea, or Lake-Sea Boundary collision happens doesn't guarantee storm initiation. It's sort of like lighting a firecracker. You watch the fuse fizzle to the very end..then when the spark meets the bomb it's either BOOM or a dud.

Storm motion will be totally contingent upon propagation and further initiation along previously established boundaries...all of which will go on away from the coast. The most likely region, but not exclusively, for all of this to occur will be over Eastern Polk, all of Osceola, Orange, Lake, Seminole Western Volusia, and within 20 miles of the shores of Lake Okeechobee after 4pm. In such a set up, it's also possible a storm could go up over extreme SW Brevard late in the day assuming that we do indeed get late afternoon activity inland that sounds a boundary back toward the coast.

TOMORROW: Will be watching for much the same developments for early in the day with similar results...but by late in the day everything will be well inland with best concentrations of rain activity further west than today.

THURSDAY - THE WEEKEND: Good bye rain chances along the immediate coast. The ridge axis which is further south will be over North Florida and an E-SE steering flow will have been established at all atmospheric levels within the boundary layer. Eyeing the SAL (Saharan Air Layer) toward weeks end currently WAY out there in the Atlantic Ocean. Will it impact Florida? If it does...say hello to the 'weather from hell' (very warm, dry, and very hazy with light wind...zzzzzz)

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Monday, July 12, 2010

"Surf's Up!" But It's a Small Swell

(Image: Averaged moisture/winds aloft show wave one is passing and another is on the horizon)
Surfers know that the waves associated with an ocean swell come in sets. The same can be said for atmospheric waves of energy associated with a storm system or synoptic weather pattern but which are much more complex due to underlying thermodynamic principles (at a bare minimum).

REVIEW & SYNOPSIS: Central Florida is in between waves this morning as a fairly rare July swell swoops overhead. The first wave of the set came across yesterday and is currently exiting the area as the next one is already on the horizon and breaking on the reefs along the Alt 27 corridor from near Steinhatchee/Deadman's Bay toward Ocala.

On a broader/ general scale, high pressure is center over the Central Gulf of Mexico with another center well east of Bermuda. The systems are just barely connected by a ridge of high pressure near the surface that runs well off the East Coast and through the Florida Straits. Over the state and north of this axis exists a generally flat to slight troughiness in the mid-levels. The source of the swell actually exists well out in the Plains region which is generating the waves and sending them toward the SE U.S. They dampen out as they approach Florida and are just barely providing us with a passing blow...but just enough of one to make things interesting (surfable).

TODAY: First off and most notable is the PWAT value from KSC's latest sounding. Remember when PWAT was down to 0.86" (dang low)? Today it is at 2.24" which is remarkable from a moisture perspective and reminiscent of the values we had two weekends ago when it was cloudy all the time. As such, it is cloudy as I write at mainly the mid-levels..but areal coverage has been decreasing during the past 3 hours per IR satellite loops.
It was quite hot yesterday in some locales with Melbourne tying a record high of 97 (Miami also tied their record high of 95). KSC also reported 97 with a heat index of 115 degrees before the storms moved in. Such will not be the case today due to the lingering cloud cover and generally 'stirred up' atmosphere overhead in the wake of yesterday's wave. Overnight low in Canaveral was 80 degrees (PAFB eked out a 78 for an hour right at sunrise) under the clouds which prevented release of the heat into the atmosphere.

Today will be yet another anomaly type forecast unrepresentative of the typical sea breeze/lake breeze initiated type least initially. Once again, we will have a later onset of the sea breeze today..but not anticipating it will be quite as late as yesterday. Somewhere between 12:30-1:30pm at latest. Highs will make it to near or slightly above 90F across Central Florida, but further south where the moisture just moved in since last night but skies are much clearer they will be flirting with records once again.

In general, skies will clear more during late morning as the first wave moves further away, heating commences, and NVA (negative vorticity advection) clears out. But the next wave will already be on the wax up. Just how this wave will break is in question though.
Everything hinges on (1): how much clearing (and thus heating) we get and thus when, where, and how strong lake and sea breezes release in earnest and begin to have an impact on the surrounding geographically prone areas, and (2): how much this approaching wave will dampen or even strengthen during the course of the early afternoon and thus stirs the atmosphere throughout the layer proportionatly.

The very general low down though is that we can expect a broader area to receive rain today. Cape Canaveral received 1.39" inches yesterday whereas areas very near by received only a trace to none. There was none south of Melbourne - West Palm yesterday as an example. But the first wave opened the moisture gates so today expect they will have a good shot at storms too...just later in the day into the early evening hours.

With heating of the day with some cloud clearing, with what's left of the approaching impulse (wave), sea breeze initiation with heating, tons of moisture around, and nearly 0 convective inhibition we can expect a shot a storms pretty much anywhere along the east coast from West Palm to Jacksonville..the further north one goes the earlier it will be.

Not expecting severe storms, but wouldn't be surprised if some SWS (Special Weather Statements) need to be issued for either localized flooding where some training of storms could occur or for strong wind gusts. On the other head, it wouldn't hurt to be aware that there is the ever so remote chance of a funnel or waterspout should the primest of small scale mesoscale accidents occur.

TOMORROW: Probably the same scenario at play but with much different potential results. For now, we'll leave it there will be another chance of storms since the swell will continue, but just how the wave breaks when it reaches the coast cannot be determined until that wave materializes.

WEDNESDAY: The swell ends and we start to return to a more climatogically generic weather pattern and surface ridging resumes in earnest initially dead overhead then further north toward Friday. There are signs that much of Central Florida could be in an atmospheric 'shut down' later in the week with no storms or showers to speak of...but at this time such notions should remain mute.

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Sunday, July 11, 2010

Will Late Morning Activity Yield To Early Evening Results?

(Image: Light thundershower today at 11am as seen from a distance to the WNW in Lake County)

SYNOPSIS: It's beginning to get progressively difficult to ascertain just exactly where the frontal boundary across the southeast states landmass even exists per latest surface observations across that region. What portion remains appears to have gone stationary and lays somewhere across S. Carolina...but the main player as far as large scale atmospheric circulations is concerned appears to be the location of the dominating high pressure axis' at various levels of the atmosphere all of which are either directly over or south of extreme S. Florida. As such most if not all of peninsular Florida is experiencing a general west to east flow along the northern periphary of the anticyclonic circulation.
TODAY: Somewhat discouraging to watch the KSC sounding data to progressively decrease PWAT values since last night despite the fact that water vapor imagery would indicate from first appearances that it would have increased. Expecting a somewhat non-typical for July pattern for today through at least Tuesday and possibly Wednesday.

As can seen by the included photograph there is some activity already to the WNW from as close as far Western Seminole county continuing NWN-NW toward Ocala and other locales yet further west well into the Gulf. The activity at this time seems to be lined up along a boundary of sorts which is progressively pushing south...especially over the Gulf waters.

Much like yesterday I'm once again expecting a later than normal onset of the sea breeze from Cape Canaveral and south . Further north it's possible the sea breeze will not kick in at all. This was the case yesterday and it appears such will it be so today as well. As a result, the temperature in Canaveral at 11am is right near 90F already without the sea breeze's cooling affects.

The rain showers further west and north actually began prior to sunrise and areal coverage has expanded ever since the initial first little shower initiated. Despite the presence of this expanding area as it approaches East Central Florida it appears that it will erode (disappear) the closer to the coast it gets due to the low PWAT values over the area. So that's it for the period heading into the late afternoon hours.

Later in the day, expect that as the atmosphere becomes more unstable with heating of the day and lake boundaries begin to interact that more storms will initiate primarily along a line from Daytona Beach to just north of Tampa which will be easily visible from Brevard. But the sun will shine throughout the day until very late in the afternoon.

EARLY EVENING: Here's where it gets interesting, but everything is contingent upon whether or not higher PWAT will sink into the immediate area by sunset. Despite how close these storms will be there will be a fine line between where it can eventually rain or not. Indications are that activity will exist in the early evening near or south of Daytona which will work along the by then developed sea breeze near the Cape and progress south into Brevard east of I-95 near sunset which could last for an hour or two after that time. The southern extent of just how far south this activity will last is being portrayed by a range of models (as of the last I looked) to be between Cape Canaveral to Melbourne Beach. Further south activity looks unlikely until one gets way down there toward West Palm Beach.

MONDAY/TUESDAY: Clumping these two days together for now because over the very broad scheme of things little will change as far as the placement of the ridge axis' and PWAT values could change significantly as moisture will be available in only unforecastable 'puddles' splattered about here and there. But the general consensus is that there will greater available moisture over Central Florida both Monday and Tuesday afternoons. With nothing really occurring to offset thunderstorm development there's no real reason why storms once again wouldn't be possible.

WEDNESDAY: Transition to a different pattern of prevailing deep ESE-SE flow at all levels particularly by Friday with more to come on just exactly how that will affect this area as the time approaches. Was going to provide a "heads up" or "this might be possible" discussion for that time frame but this has already gotten too long winded. Leave that for another day and page to turn in the continuing saga.

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Saturday, July 10, 2010

Minor Changes Yield Minimal Results

(IMAGE: without availablitiy of the KSC sounding, we resort to the less-than-impressive Tampa one)
Sometimes a minor atmospheric change can significantly alter the weather for a specific locale, but that is not the case for today (at least not at this local level).

THE SYNOPSIS: On the synoptic scale everything is materializing as anticipated yesterday. The low pressure system that was just off the North Carolina coast is moving NNE pretty much parallel to and just offshore the coast. This system will continue heading toward coastal New England as it becomes essentially entrained (absorbed) into the midlevel trough and associated surface cold frontal boundary by later today during the course of its journey. The surface front is now almost right on the coast for the NE states but drags back toward the SSW-SW-and eventually west as one heads south through Virginia, the Carolinas, and into north central Georgia, Alabama, and Mississippi. Meanwhile, high pressure has the expanse for almost the entire Southern U.S. from the Florida Panhandle, along the Gulf Coast, across Central Texas, and west to Arizona. The trough along the U.S. East Coast has temporarily put a minor break in the ridge strength over Florida and pushed it well south toward the Florida Keys. As such the low and mid-level flow is from the SW.

LOCAL ANALYSIS: I was not able to obtain upper sounding data from KSC (XMR) this morning as it hasn't updated since yesterday morning on the internet (sob). But based solely on the latest satellite imagery / model initialization/ surface observations / and local visual clues observed upon looking outside it is apparent that the suppression and drying affects from yesterday's ridge placement aloft has proportionately abated as the axis was dislocated south of the immediate area over night. The NWS MLB apparently still has the goods on the sounding data though, and per what could be picked out of their discussion combined with water vapor imagery it's safe to say that PWAT values have increased since yesterday in the mid-upper levels although the temperature there is still on the "too warm" side for robust convective initiation and sustenance. Additionally the lazy, hazy look to the sky has decreased and thus visibility has gone up.

TODAY: With placement of the ridge axis further south we have a morning land breeze. Models are all showing a SW-WSW flow to persist through the next 48 hours at least, but I believe that the pressure gradient at the surface will not be strong enough to maintain that wind component once the land/sea thermal gradient and resultant pressure patterns gets established. But it will take a while for the synoptic pattern to be overcome. In other words, a late start to the sea-breeze which yesterday commenced during the 12:00 noon hour. Thinking now is the sea breeze will not commence until 1:30-3pm. As a result, even the A1A corridor will feel the heat pinch with high temperatures solidly in the lower third of the 90s if not a degree or two warmer than that.

Rain?! There is actually two periods at which we could get the smallest of chances of rain today. Period one is contingent upon if the sea breeze starts up as late as was just hypothesized. If it does indeed hold off until later, there will be a chance some showers could go up right along the immediate east coast as far south as Martin County (near Palm Beach) within the first hour of sea breeze initiation due to coastal low level wind convergence, the longer time for instability to amass, and the slight increase in atmospheric moisture which has occurred over the past 24 hours. The folks further south by Martin County will have the added benefit of a Lake Okeechobee/Atlantic breeze collision but moisture is lacking more down that way so this is questionable for them. The second period will be when the west coast sea breeze has worked across the state and confronts the east coast sea breeze which, assuming it does indeed initiate, will be east of Orlando close to I-95 during the early evening hours (post 6:30 pm - 9pm). This activity would drift slowly back toward the coast as well anywhere from southern Volusia through Indian River Counties.

TOMORROW: Looks like a repeat of today with only localized parameters and subsequent atmospheric adjustments in the level of available moisture during the course of the next 24 hours being the factors needed to ascertain just exactly how, when, or if we will have rain chances and if so, how high they will be. For now, if we rely solely on last night's model runs..the chances for rain tomorrow look bleak at best.

EARLY THROUGH MID NEXT WEEK: The ridge axis will remain to the south through Tuesday then progress north to Central Florida by midweek. Although steering currents appear as though they will be less favorable for the rain chances along the barrier islands on Wednesday they could very well increase for folks west of US1 since it will bring a return to higher PWATs upon its return.

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Friday, July 9, 2010

Warm, Hazy, and Primarily Dry in the Rain Department

Essentially no changes in the line of thinking from yesterday's rambling. The low pressure system that was near Bermuda several days ago continued to move WSW as was noted previously and is now rotating just off the North Carolina coast to the north of Cape Hatteras. The circulation is readily apparent both aloft and at the surface via every form of satellite imagery and surface observations. A cold front extends NNE to SSW from NE Ohio, through Western Kentucky and Tennessee, and south into Central Mississippi. Ahead of this front high pressure at the mid-levels is spread across all of the northern Gulf from Eastern Texas eastward across all of North Florida. Central Florida is under descendant motion around the southern periphery of this high pressure bubble for the day.

At first appearances it seemed that things would be fairly primed for storms today, or at least headed in the right direction for them by around sunset, given the current stability indices and the fact that the PWAT level has gone up from yesterday's low value of 0.86" up to 1.56" as of noon time. But a lot of that moisture is trapped below the mid-level ridge axis mentioned above (which is visually apparent by the hazy/dull look to the sky). Additionally, the convective temperature is around 99F which simply is not going to happen. The presence of this high pressure is even more apparent across North Florida where the heat is on and the air is even drier (thank goodness for small miracles otherwise the heat indices - the apparent temperature - would be at the meltdown level up by Jacksonville as if 97 degrees alone isn't bad enough).

TODAY: After a morning land breeze (from the west)...the A1A corridor is now working on a sea breeze with winds from the ENE north of the Cape (Oak Hill) and ESE-SE winds south of the tip of the Cape (Cape Canaveral southward). Expect these 'cooling' winds to maybe make it as far west as Orlando by early evening. Inland afternoon temperatures will be in mid-90s and probably feel pretty darned uncomfortable with little in the breezy category to provide evaporational cooling from the sweat glands. This is the kind of day that Wet-n-Wild was made for. About the only thing to look for is if some rain showers go up in Northern Osceola County to very near Orlando and maybe western Seminole County region within an hour or two of sunset. Maybe those folks will luck out. Maybe not.

TOMORROW: The atmosphere still has some work to do to recover to operable levels...but the antidote won't be arriving by tomorrow afternoon; thus, we'll sit yet another day in the waiting room and pray for the best for Sunday. In other words it will be much like today. About the only difference is that at this time I think tomorrow will be the warmest (might as well say "hottest") day of the weekend and upcoming week for our land-locked neighbors.

SUNDAY/MONDAY: The cold front will work it's way into the southern Deep South and begin to align in an east-west orientation as it lines up along the remaining ridge over Florida, which by the way will also be pushing down into extreme South Florida. Looks like what is left of the front will grind to a halt across Southern Georgia and Alabama while the ridge axis will line up across the state from roughly Miami to Naples with its western extent well out toward the central Gulf, at least initially. Such placement of the ridge (assuming this is what will occur) does not exactly place us in a favorable position to receive a moisture feed from the tropics to juice up the atmosphere. Regardless though, the subsidence (descending motion) should abate and place us in at least neutral to positive relative upward vertical motion. Additionally, some pockets of moisture will gradual sneak in during the course of Sunday and Monday which through virtue of the nature of the Florida Peninsula and its sea breeze/Lake breeze collision reputation will finally take the storm gods off the gurney.

But back to full-bore climatologically normal levels of liveliness? At this time it's not looking likely...not until the ebb and flow of global atmospheric eddies makes some additional adjustments. They'll come...eventually...but for goodness sake "Will storm season ever arrive in earnest this year?!".

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Thursday, July 8, 2010

Holy Smokes - It's Christmas in July

(Image: Surface temperatures at 6am delineate our "Arctic" plunge)
Can you believe it? Did you feel it? It's actually 'cool' outside this morning by our summer standards! Temperatures right at sunrise are as cool as 66F at the Space Center and Melbourne is at 69F which is just one degree off from tying their record low. WOW. I noticed the difference immediately upon stepping out the door at sunrise. Was looking around for some fluttering snow flakes to catch on my tongue but only swatted at buzzing mosquitos.

REVIEW: In some ways, it's not entirely a total stretch of the imagination to believe that a 'backdoor front' of sorts went through in conjunction with a mid-level wind surge from the NNE yesterday that occurred at 1:10pm. I noticed a line of low topped cumulus and some widely dispersed very light rain showers offshore accompanying this line of clouds along the leading edge of this "impulse" per se. There was a VERY long, dangly rope cloud formation on visible satellite imagery that was quite discernible accompanying this atmospheric transformation which extended several hundred miles east of KSC way out into the Atlantic. Wish I had saved the satellite image. These formed along the leading edge of drier air moving in at the mid-levels along with the slight / temporary pulse.

The end result this morning is easily seen on the porch thermometer as well as the latest sounding where PWAT has fallen to an unseasonably low level of 0.83" (down from 2.00" + inches just 2-3 days ago) and winds at all levels are from the ENE-NE. It is likely that it's the low moisture level that is truly responsible for the low'ish' morning temperatures which is allowing heat to escape into the atmosphere. Within the hour it will be just like any other day temperature wise once the sun comes up in earnest.

SYNOPSIS: Low pressure is still retrograding WSW-W toward the North Carolina coast this morning but is doing so slower than earlier anticipated. Circulation/subsidence around this low and high pressure over the land mass of the mid-Atlantic is creating the dry NE winds aloft over all but extreme South Florida (where rain showers abound across the Keys) and such will be the case for the remainder of the day. This same system could be responsible for some strong storms today particularly for eastern North Carolina where the presence of this same low pressure system will create speed and directional wind sheer over a developing lee side trough during the afternoon. Lapse rates are not forecast to be particularly steep though...and moisture isn't the probably the biggest threat would be strong wind gusts in the strongest of isolated storms.

TROPICS: Tropical depression formation was officially proclaimed just about 2 hours ago in the extreme West Gulf. This low appears as though it will landfall near Brownsville in extreme SE Texas. Its circulation is barely visible on IR satellite imagery or even water vapor loops...but is evident on radar to some degree. It won't take much for it to become Tropical Storm Bonnie...but what a waste of a name. Whether it is a low end tropical storm or not will be strictly a matter of naming a closed circulation for the most part since not much more than minimal intensification appears likely. Regardless, it will be bringing more rain to already saturated soil which is not good for the already flooded folks in south Texas where rain has persisted since even before the passage of Hurricane Alex last week.

FORECAST: The low off the mid-Atlantic coast will slowly approach the North Carolina/Virginia coast then merge with a front/trough which is approaching the NE states as we speak. Say goodbye to the heat wave in the Northeast at long last by tomorrow. The low will essentially become absorbed with the front as it takes on more of a northward drift in the process. The base of the trough will deepen into Georgia then move east and begin to lift north as we work into next week. As a result of the trough..a high pressure ridge will be shunted south to South Florida where it should remain through Monday and into Tuesday. This will provide for a SW-WSW steering flow over Florida which normally I'd rejoice in with anticipation of inland thunderstorms being steered toward the coast. One problem though...the air mass does not look like it will particularly moist given the wind trajectory aloft...but this could very well change so let's just wait and see for another day or two.

TODAY: Dry and mostly clear with a scattering of low topped cumulus at best. Despite cussing and cursing data and models I see no features at the surface or aloft to discuss. Just can't squeeze water out of a rock.

TOMORROW: Ho hum...Arizona comes to Florida. More of the same but warmer inland with highs around the 95-96 degree range. Granted, not as hot or dry as Arizona, but you get the drift. Zzzzzzz....

SATURDAY: By Saturday and particularly Sunday the coast will feel a notable temperature difference particularly around noon time when I believe at this time that a morning land breeze (yes, at least we'll have one of those at last) will be slow to wane and allow temperatures to rise above what they have been for quite a while before the sea breeze kicks in. Rain chances pick up from Ft Pierce and points well as along the Panhandle, but the immediate Central Portions might still be hard pressed to wring out a storm from the atmosphere. I'm playing the pessimist though in regards to there being very little chance of rain.

SUNDAY/MONDAY: The big question mark period in regards to storms. Granted, the atmosphere will have moistened some by then pretty much statewide...especially in the North third of the state closer to the low pressure trough in that area...but moisture from the south will be slow to arrive in full. Or will it?

We could actually end up in a phase where we have storm well to the north and south with nothing in between (Central Florida)...other than isolated activity that would pop up where boundaries collide in the vicinity of the larger lakes or where the sea- breezes collide well inland. We'll just have to wait and see how things evolve during the next few days.

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