"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".

Friday, September 1, 2017

Frequent To "Excessive' Lightning In Storms Possible Later Today

Leading Arcus Extension of Storm's "Self' Invades  Cape Canaveral on August 29, 2014
TODAY: Not much change from yesterday's thinking. Pattern of the days of the past week proved itself to be changing late yesterday, but more so well past midnight as storms continued to be generated and even move off the east coast north of Brevard County with a last little dog leg working down to Cape Canaveral around 3AM over the intracoastal - before the 'fumes  from the heating of the day' had been exhausted. Activity likely was abetted by slightly cooler temperatures  and  upper level divergence  per latest Mesoscale model plot late this morning.

TODAY: Cooler air 'up top' (aloft) is 'anticipated' though the morning sounding at KSC shows that is not the case; at least from which would not warrant for much beyond garden variety thunderstorms with a 700mb temperature of 10C and 500mb no cooler than a -6C. 

The 700mb temperature might not drop all that much today but the 500mb would begin to go down after noon or so to around -8.5C. Much to say today in favor of strong storms mostly due to frequent to excessive lightning and heavy rainfall in short amount of time leading to localized short term flooding in prone areas if late yesterday is to be taken as an indication; on the other hand, if things do not come together as anticipated it might just be like another summer day, especially since 700mb will remain rather on the warm side. 

All in all, for now anticipating that the peak convergence of outflows from the north and west and the weight behind them meeting up with the east coast sea breeze which as of now appears will make it about 20-25 miles inland (tops) if not much less across Central Volusia and northward (but further inland toward South Central)   would begin to the north first then work south and increase in generally over more areas after 3:30pm  - and of that,  could 'peak out/ over Central Volusia and southward toward Central / Eastern Osceola County, Orange County , Seminole County, Northern to Central Brevard County then on down to South   Brevard  and Indian River much later in the afternoon.

Further south other  activities could also form as a result of the Lake Okeechobee/Sea breezes along with the potential for outflows from the north to work south. All in all could be seeing lightning in a few locations well after dark, mainly over South Central Florida to offshore.

SATURDAY: There will be a difference on Saturday with possibly a bit less coverage and not quite as much intensity. Better coverage appears will be from Southern Volusia County southward, especially South Central Florida late in the afternoon. Always a chance that the more 'Central Region' might see more of a relatively, 'early onset day' as opposed to very late in the afternoon.

SUNDAY: GFS and to some degree NAM guidance appears to be agreeing on a remnant boundary across Central is where moisture will be the greatest. Overall state coverage goes down significantly , with the best focus apparently on Central Florida , even to the coast or just in from the coast for showers/storms after 4pm to dark. Nothing 'strong' per se is foreseen on this day .

MONDAY: Though activity could be about, it will mainly be well inland toward the west coast; there is a marked decrease on Monday for the most part.

TUESDAY/WEDNESDAY: For now will say either Tuesday or Wednesday the coverage might well increase, perhaps significantly from Monday as a frontal boundary associated with an upper level trough works into the Southeast States and flow becomes more southerly to even a tad SSW aloft. GFS was showing 'that day' to be Wednesday but recently points to Tuesday. A bit skeptical on that but it's several days away anyway with plenty of time to reassess.

It is this same 'Trough-iness' over the Eastern U.S. and down to Florida   that might have an influence on the future track of Hurricane IRMA.How long it remains in place, to what depth south it extends, and how far south Irma actually is on perhaps Wednesday could all be factors on the future track of the storm as well as how well the ridge to the north of the storm maintains its western most grip. Any relaxing of the ridge to the north to provide a northward escape which the storm can 'touch' will certainly take. 

On the other hand - until all things become self-evident  would expect model guidance to go back and forth in various ways as to the extended range forecast in all kinds of fashion. Point being not to hedge one's bets on anything  at this point.

Beyond IRMA there is one other system that perhaps might come into view in the next two weeks...somewhere along the same latitude as where IRMA is not located and well east of the Virgin Islands.

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Thursday, August 31, 2017

"Strong" Storms "Possible" Friday - Saturday

August 29, 2016 Off Cape Canaveral

TODAY: One more day of slightly warmer than normal temperatures as air mass modification begins the slow, post-tropical translation through the vertical extent of the atmosphere. 

Temperatures aloft remain in that way of warmer aloft as tropical air-masses are. On the other hand, with the wind fields of the past days having been resolved away which prevented sea-breeze/lake breeze convergence manifestations, we should be able to realize a better chance of storms or showers later in the day near the I-75 to Route 27 corridor and northward all along I-10 where showers and thunder are already underway.

Wouldn't expect 'wide-spread' thunder to be at hand. Better chances of 'thunder itself. appears to be over Southwest Florida northward toward Lake County (in general) with the better 'late day' chance in the more northern arena.

FRIDAY-SATURDAY:  "Summer Resumes" - For now will take the 'sweepingly broad over-generalization' approach to these days as there are specifics being implied by guidance that could potentially put a major crimp in the forecast, especially in the areas north of I-4 where cloud cover 'might be more prevalent' throughout the day. Big 'if" though. So for now...

Upper level temperatures , especially at 500mb are forecast to cool toward the -8- -10C realm with mid-level temperatures a bit slower to catch up (if at all). Additionally, there are implications of the upper levels being nearly saturated the more north of SR 528 one goes. which could mean that cloud cover could hinder 'strong' storm development in those areas. 

The issue further south is a remnant dry layer around the 700mb level. This could either hinder storm strength or add to it, depending on how vertically deep that layer will actually end up being.

Regardless, given continuity in the GFS model going into two days now and between 4 model runs will load the gun and prepare to pull the trigger on making the 'Stronger Storm' call. 

Was tempted to write 'even isolated marginally severe', especially near I-95 from Ormond Beach south toward Vero Beach late in the day" but that might be over doing it a bit. 

Either way...for either one or both days...shower and cloud coverage will be increasing..most persistently it appears over the the northern 1/3 of the state, where even pre-dawn showers with thunder might be in process near the big bend and into the pan handle regions.   

South-Southwest Flow to Southwest will be in place but not so strong as to prevent the east coast sea breeze from forming and making progress toward I-95 as it appears now. Overall, Saturday does not look like a good day for late - day activities.

SUNDAY: Temperatures aloft warm as light easterly flow resumes it's course. Moisture availability becomes much more 'spotty' in nature so making a call as to where rain may or may not fall becomes increasingly difficult. 

Overall, chance of earlier day (pre-sunrise to late morning) showers might be in the calling for certain areas along the east coast,  working inland and increasing toward the west coast later in the day.

EXTENDED: The general pattern noted for Sunday persists through at least Tuesday and/or Wednesday. Latest GFS shows an early season 'cold front' making the sweep into the Deep South, even Northern Alabama, Mississippi, and Georgia regions. If so, a more 'thundery' pattern state-wide, even perhaps toward the immediate east coast might enter the picture. Assuming the GFS is correct.

"IRMA": Seeing talk wide and broad over the internet concerning how this Storm System 'might' be a threat to almost anywhere along the U.S. East Coast. In some regard, suspect some of the amped up chat is due to Harvey's Impact and fears of 'more of the same' are at the fore-front; however, those fears do not make anything else any more or less true than would be the case for any other system, whether Harvey had been or not.

As of early this morning, the only model that shows a potential 'threat' to be the case out of several that I've looked at is the ECMWF (European) model. The CFSV2 model shows a similar more southerly track toward the Southeast Bahamas  with the storm being approximately 120 NM east of Cape Canaveral next Saturday moving northward...other guidance points to more of a threat to Bermuda and possibly the Northeast States (if even that). 

Point blank, it's just too soon to say, and that a 'threat' is not utterly out of the question.

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Sunday, August 20, 2017

Dry For Eclipse Monday : 'Unsettled' With Rain -- Storm Chances Tuesday & Beyond

"Arcus Accessory on the Archway!" - Canaveral Cruise Terminals -
Friday, August 18, 2017

An unsettled weather pattern of showers and thunder being possible (even at times over night (especially over the Atlantic) with some 'early on-set ' days possible with varying others modes of operation at hand beginning mid-day Tuesday or as late as earlier on Wednesday through end of month (a few details further in post) for today...

SUNDAY: Remnants of a tropical wave already encroaching in on the southeast 1/3 of state to glide over the state today mainly south of I-4.  Wind will be light in the moisture laden air-mass though mainly east to southeast up through the column less than 12 knts.  Guidance is split on how far 'east and north' rain could occur today with greater agreement that points to Southwest Florida.

The area from mainly Indian River and Brevard toward Osceola and eastern Orange Counties is a 'questionable region' in regard to whether they will experience mainly cloud cover or actual rain-showers/storms. The HRRR (High Resolution Rapid Refresh) model is consistent on saying 'no chances' (at least early this morning) whereas the 4KM NAM model for the same time is and has been  consistent on saying 'Yes' to the chances for this AOI (Area of Interest). 

The greater chance of storms/ rain for the mid-late afternoon is along Southwest Florida where the best chance of the combination of moisture and low level convergence along the West Coast sea breeze will occur. 

If the areas of Brevard/southern Volusia/Indian River and maybe even St Lucie are to see showers/storms it would be from south to north between 11AM heading toward the 2pm hour (generally speaking).

MONDAY: Sunday's activity will be the first in the next wave of the set to move in, which is on Tuesday. Between waves will be a lull in the action. Enhanced water vapor imagery clearly shows the respite timed nicely for "Eclipse Monday 2017". GFS does show rain storm potential however earlier in the day with a rapid decrease moving to the 'critical eclipse time-frame' of early to mid afternoon as the remaining moisture from Sunday's wave moves west and out of the picture. 

With that said, not to be surprised (just in case) if showers and cloud cover are still sensible (especially along the east coast) early in the day on Monday.


Expect forecasts to shift around rather significantly , almost on a daily basis,  from Tuesday on out at times due to the uncertainty of where, when, or even if an area (or areas) of low pressure might form, especially in the Wednesday - Sunday time frame. 

 A rather complex scenario is at hand in regard to surface and mid level features in regard to the evolution of circumstances, though there appears to be agreement. more or less. that abundant tropical moisture in the mode of PWAT air (precipitable water) values being near to well above the 2.00" mark (comparably speaking, in winter months it is normally 1/2" - 1/4" (or even less at times - aka 'dry air'))

The onset of the moisture is along the leading edge of an AOA being watched by the Hurricane Center which is not forecast but by one model to develop beyond an 'organized wave'. There does seem to be some agreement later on though after this area moves over the southern 1/2 of the state that a weak surface to even mid-level area of low pressure will form either over or just to the east of the state, but it's just too soon to say with any confidence if , when, or where that might occur.  

Apart from a wide mode of potentialities, regardless of what transpires there has been at this point no risk of a bona fide 'tropical threat' outside of perhaps what eventually might evolve for some areas of localized flooding in flood prone areas due to heavy rainfall (mainly during the afternoon and evenings) with consecutive convective days occurring back to back. And if a system does evolve into the realm of the naming convention type it is seen so far to do so east of the state and remain far enough away to not have a direct impact.

Arcus Shelf Accessory from Parent Thunderstorm over the Banana River - Port Canaveral, August 2017

Initially rain fall could occur most anywhere at any time (though mainly later morning through late afternoon) south of I-4 (Tuesday/Wednesday time frame), but as an upper level trough builds south from northern latitudes in response to ridging over the Western U.S., the steering flow becomes progressively more southwest toward the northeast especially as we head  into Friday through Next Weekend. If a low pressure area does form east of the state there could be one or two days of decreased activity with northerly flow to the west of the system, but it's too far out in time to hedge any bets on if that will occur; so far , even if that does occur as the GFS has been implying, moisture is foreseen to remain ample from 'some rain' chances even if so .

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Wednesday, August 2, 2017

Emily's Offspring to Provide Rain to North Central - North Florida

"Rain-Storm" - July 28, 2014 Near Satellite Beach 
TODAY: Things have changed rapidly (though not unexpectedly) overnight. A surface boundary associated with departing Emily left a surface front across South Central by late yesterday. That boundary has retreated as a 'warm front' north to almost I-10 as of 10AM.   South of the boundary, as can be seen below, Emily's offspring in the form of a 'vorticity max' (more than one) is on the trail toward North Florida today, with another apparently awaiting in it's wings for tomorrow further to the Southwest over the Loop Current. What exactly will occur with that is questionable, but for today...

Cloud cover already beginning to over-spread areas that were earlier thought might see a 'good shot at thunder'  so earlier model runs to be tossed. How pervasive the in-coming high - mid level clouds into parts of Central or even South Central  will determine where, if any where, strong thunder will be realized, if in fact, much at all.

For now based  on watching satellite loops , and based on latest wind-profiler information from around the Space Center along with surrounding Rawinsode Sounding Data out of MIA and MLB will go with increasing cloud cover especially along and north of I4. Chance of thunder there still exists but am hesitant to call for 'stronger storms'. Further south and east the chance might improve depending on how much prolonged insolation is received before 2pm or so.

Steering for rain showers and storms is from the WSW-SW at around 17kts from cloud base on up into the mid levels but not strong enough near 'the deck' to off set the development of the east coast sea breeze from Daytona and South. Thus, rain-thunder storms to move easily from west to east today and straight off the coast. Best guess for now is that the east coast sea breeze will form but remain close to the coast, especially for Brevard / Volusia. Best area of insolation and sea breeze/outflow convergence appears to be the coast of Brevard and Indian River Counties then curving inland a bit toward northern side of Lake Okeechobee, and western half of Martin County. Other storms could form further south from St Lucie County to Palm Beach, Broward and Miami/Dade.  

Hazard mainly would be lightning as usual, and heavy rain. Thankfully the majority of the largest rainfall totals appears to be over areas that were least impacted by Emily the other day, though areas that did receive high totals will still see more rain chances today and tomorrow to add insult to injury. Outside of the pervasive lightning threat, stronger wind gusts could occur in the area in 'red' (only as an example). The area in purple is highlighting where it looks like the highest two day rainfall today will be.

THURSDAY: Again, a somewhat similar situation at hand that will likely evolve in a different way. Drier air is to   advect  around the west side of High pressure building in from the Western Atlantic first to South Florida then up though all of South Central by late in the day. Though there could be 'some rain ' in those areas though not very likely but in isolated cases, the better chances for thunder/rain on Thursday appears will be along a line running from near Palm Bay toward Sarasota and north..with an even better chance along and north of I-4 (generally speaking).

FRIDAY: Looks so far like a 'dry slug' will move in with most rain chances restricted to North Florida.

SATURDAY: Shifting again to respectable thunder /lightning risk in what appears to be a  'typically on the wetter type of 'Summer' type of Day ' regime as the ridge axis continues to lift north from South Florida to Central Florida. 

SUNDAY: Same regime as ridge lifts even further north. Rain chances from here on out going into at least mid week next week go down appreciably many areas. Some consecutive dry days in some areas are thus forthcoming. possibly for nearly a week toward next weekend at the rate it's looking now...with most rain chances restricted to SE Florida in the mornings and the interior and west coast in the latter parts of the day.

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Friday, July 28, 2017

Chances of Thunder 'Mainly' Along to South of SR50 Through to the Glades - Hot Inland (!)

Severe Warned Thunderstorm near OIA
Viewed from the Brevard County Line to the East

TODAY: Not much change from yesterday though KSC sounding appears to have come in just a tad cooler aloft. The other change is lack of upper level cirrus clouds that were prevalent yesterday which had streamed across from the NE from storms that were well offshore the coast of North Florida. Net effect will be better surface heating today in the presence of PWAT air in the 1.7 -2.10" range across most of Central/South Florida.  Guidance originally had almost zero chance of rain north of Indian River County but that might have changed from what I'm seeing from morning surface obs and latest HRRR run. With that said, the region that there is most question about in regard to if it will rain (or rather, thunder) other than an isolated shower or two is the area north of far Southern Brevard County. More certain seems to be points south and inland.

Otherwise, again warm with high heat indices. Highs running lower 90Fs near coast and in the 94-96F range inland (maybe even warmer a few places?). Otherwise, it will be similar to yesterday. The lack of early day clouds though will certainly give things a head start in the heating up realm.  Though there could be showers or even a storm near I-10 today I left that out in the graphic below as it looked to be a very 'isolated' situation up that way today.

SATURDAY: Again, a lower end chance of rainfall overall by July standards. Guidance still comes in rather 'dry' but not completely. My guess is that this day will have the least chance of rain of any day to come for quite a while.

SUNDAY-THURSDAY: As mentioned in previous post, a near FLT (Full Latitudinal Trough) up and down the east coast is shaping up and looking more unusual with every passing model run it seems. 

The associated cold front which was being advertised yesterday to make it 'possibly' as far south as I-4 is now being shown per overnight models at least to make it into North Brevard County - possibly somewhere near SR 50 across toward Brooksville on the west coast. At this rate, it might even make it down to Melbourne or so if the trend continues. Either way, that boundary should act as a mechanism for convergence . and anywhere within 30-40 miles either side of it could see a high chance of rain. Wouldn't be surprised if we see or hear 70-80% chance of rain on local net works come Monday night through most of Tuesday and into Wednesday. The days will not be complete wash outs, but likely have sig cloud cover off and on with a quick start to convection and showers after sunrise. Either way, no matter how far south it gets it is expected to take a slow lift back to the north by Wednesday afternoon.

BEYOND: Continued high PWAT air (reading above 2.00" through the duration from late Sunday through Thursday at least. If you can believe it, the last GFS run showed PWATs running at 2.00" plus for Central and South Florida through August 6th or a good 10 days. For comparison, in the winter months our PWATs run around 0.2 - 0.5 "  . Here is a colorized graphical depiction for MONDAY's FORECAST per the GFS of the Precipitable water values being forecast. The white boxes are showing the PWAT being forecast for various areas. The 'blue dashed' line is an estimate of  where the SURFACE FRONT might be located Monday afternoon, which will mostly be but a wind shift line though we can see there is drier air even across Far North Florida behind the front. For the most part, anywhere south of a line from Ormond Beach toward Cedar Key should remain in the realm of rain chances every day from Sunday through next weekend, and with that, not so warm as the past few days and today.

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Thursday, July 27, 2017

Greater Storm Coverage Today - Very Warm Friday/Saturday Even at the Coast - Then...

Vertical Standing Shelf Cloud Moves In -July 26, 2014 Cape Canaveral
 TODAY: Day 2 of same theme, only with a bit more moisture  with slightly better wind fields to work with. Mid-level area of low pressure slowly taking shape over the Deep South as upper level trough moves east through the Great Lakes region to eventually sync going into Sunday-Tuesday time frame. But for today..

More warm temperatures before rains develop with high heat index readings. Best chance for convergence of sea breeze boundaries appears will run a line from JAX along the St. John's River Valley basin through Central to Western Volusia , down toward Eastern portion of Osceola County and take a curve toward the WSW-SW to near the Fort Myers area.

Largest rainfall totals appears will occur from near SR 50 and north. Though there could be an isolated stronger storm the bigger news will be lightning and larger rainfall totals near or west of I95 suspected somewhere near Seminole County, perhaps eastern Orange into parts of Osceola County. Best opportunity for storms to clear the coast is from Volusia County and north though some activity in a weakened state might be able to drift offshore from near or north of Melbourne Beach.

FRIDAY-SATURDAY:  Next pattern begins for two days. Pressure gradient to increase from the SW direction. The east coast sea breeze might be held off until mid afternoon north of Vero Beach (or so) which , if so, could take temperatures even at the beaches from say Cocoa Beach and north into the mid-90Fs. The sea breeze might not manifest at all for Volusia County and north.

Historically, a 'good SW flow' at the surface in the absence of cloud cover tends to pile up the heat along the far eastern side of the state north of Lake Okeechobee. Gander  that from Ft Pierce and north might see some solid mid 90Fs..whereas further south the better chance of showers/storms (St Lucie County and south).

 There will be little if any storms around Central though never say never, it just looks slim.

SUNDAY-WEDNESDAY: Pattern change. Low pressure over much of the southeast places Florida  clearly in cyclonic flow aloft and at the surface. Sunday is now coming into the picture as an active day along with Monday. 

The Frontal Boundary associated with the  developing synoptic scale scene is expected to make it as far south as potentially I-4; even a 'cold front' as far as July standards are concerned. 

(Morning temperatures further north over the region along and east of the Mississippi are forecast to fall even into the lower-mid 50Fs in some areas; meaning some areas that were hit hard by heat not too long ago such as Tennessee will now experience a flip-side)

On this Date in 2014, Off Cape Canaveral
TUESDAY and WEDNESDAY will likely follow along similar themes but exactly what that will be is hard to say. Temperatures beginning Sunday or at least by Monday will not be nearly as warm due to increasing cloud cover, as rain chances will also have increased. Working into Tuesday the flow increasingly becomes more WSW - West with much lower chance of sea breezes (probably none). How cloudy it will actually be though could well determine afternoon rain chances and locations. Thunder will still be possible. The GFS implies Tuesday is more or less a 'wash out' for some areas or perhaps just a  'cloud out'...

BEYOND: Pattern continues to remain 'unsettled' (to put it lightly) all through to Saturday of NEXT WEEKEND after this upcoming one. 

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Wednesday, July 26, 2017

New Pattern to Play Out Today - Thursday

Storm Approaching Canaveral Cruise Terminals on Sunday Around Noon-Time
TODAY-THURSDAY: Twist to the rather uneventful pattern of the last two days (Monday/Tuesday). Not that there has not been some showers, and even a 'good rain' the other day down in Okeechobee County, but by-n-large things have been on the 'quiet but hot' side of the July coin.  Looks like it landed on tails the past couple of days but it will all come to a head coming late week on the flip side.

Regardless, minor detail changes at hand but nothing that will go unnoticed for those who get a shot at rain today that haven't even seen a hint of it during the past two days. Will not rehash the warm and hot message that most are already aware of if only to have walked outside after 1PM and away from the sea breeze, as heat indices sore to even above 108F in a few isolated cases, but mostly around the 102-105F region (other than right on the beaches).

Moisture most available across South Florida will advect during the day to near the SR 528 dividing line by later afternoon. Sufficient moisture in place already for some cumulus clouds but nothing more that far north (so far), whereas a few showers have already managed to develop over South Florida.

Though a storm could 'conceivably' become strong, the signals aren't good enough at the moment to make that call, and nothing per guidance implies that would be the case if in fact given the atmospheric conditions it is even possible.

 Most activity will be in the 'shower' category for the most part , apart from boundary collisions near Lake Okeechobee and late day where the 'Hatfields meet the McCoys" (West and East Coast Sea Breeze Collision") where some real 'sparks might fly and shots will be fired'. 

 Best chance of this collision appears now to be in Central Osceola County  then south and west toward the NW-and West side of Lake Okeechobee.   

One model shows some stronger activity closer toward the West coast even well South of Tampa but am hesitant to include, namely because upper level winds at 'storm anvil height' are well  out of the Northeast to ENE and blowing toward the WSW..anvil tops spreading across the western portions of the state if other activity forms more toward the interior might well put the lid on activity further west.

THURSDAY: A similar scenario will take shape, day two of the Pattern with a variation. This day appears to have better coverage and greater storm strength potential. Some activity on this day might be able to work off the east coast from Brevard County and North as SW Flow aloft begins to increase.

As it is now, a voriticity field aloft is resting over Southern Georria toward North Florida. This area appears to be the harpbinger of what is to develop in the coming days as an upper level trough well up by the Great Lakes moves east and begins to synch with the mid-level  'troughiness' over the Deep South just now in progress.

FRIDAY-SATURDAY: These two days might be the great 'in-between' days of lower activity again as drier air advects across the state.

SUNDAY-WEDNESDAY: These days, but mostly so on Monday, appear to be the next pattern to emerge   as a near Full Latitudinal Trough (FLT) down the east coast with a mid level Center over the Deep South will increase westerly flow surface and aloft. By Tuesday and/or Wednesday we might not see an east coast sea breeze at all. Despite that there will be increased moisture ample for storms, that which is being most impressed from my readings of the models at this stage is for early morning activity mostly over the Panhandle and along the Gulf Coast...with increased could cover from the west spreading across much of the state. After Monday it might be hard to recover from the previous day's activity, and so it goes on into the following days, each day successively less active than the day before due to cloud cover even though steering would favor storms moving completely off the east coast of the state.  

That is just a first 'best guess' as to what might begin to evolve going into later next week; for now though, perhaps on Sunday we will see stages of the new pattern at play to evolve to Monday and perhaps Tuesday. Long and short of it is that next week might not be the greatest days for going to the beaches other than earlier in the day. Monday appears to be the biggest 'overall  Thunder Day'.


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Saturday, July 22, 2017

Storms/Shower Risk Today Up and Down the Peninsula - Even the Beaches (?)

Over the Banana River on this date, 2014
TODAY: Same general synoptic situation is at play but with a slight change in the theme as the old one likely played itself out yesterday with the very early onset across SW Florida associated with colder air aloft - that as a 'renegade' upper low had retrograded from the Carolina's the other day toward North Florida and continues west and out of the picture.

New scene today as temps aloft are just a bit warmer  with the low having moved further from the state -   upper level triggers (vorticity) associated with it are likely more removed from the immediate area (as per model guidance).

Otherwise, Cape sounding showed a convective temperature there of 90F which is up a bit from yesterday, and warmer by about 2 degrees at both the 700mb and 500mb levels. Steering is from the southwest but not so strong as to prevent the east coast sea breeze from forming.  

There  is activity up and down the west coast however encroaching on to the beaches in some locations. Chances are if these storms can collapse and send outflows eastward coincident with the west coast sea breeze, that boundary could make good headway toward the east side of the state while the east coast sea breeze makes much slower progress. 

There is some 'cloud cover' across a portion of southeast Florida which 'might' put a crimp in the storm style down there (if any is to be found at all, 'see below') apart from a merger of the Lake Okeechobee/Sea breeze. That area looks like it might escape the storms today, unless the clouds thin out a bit (hard to say for certain).

Otherwise, apart from other questionable potentials ...the 'better bet' (per the blogger only) for mid-late day storms appears to be along I-10 then south along and west of I95 as depicted below.. also activity could 'pop' as the east coast sea breeze forms but suspect it would be rather isolated, at least compared to yesterday's standards.

The region over South Florida (south of Lake Okeechobee) will likely need to wait for the sea breeze collisions later in the day as well; the Miami sounding had a precipitable water value of around 1.72"   (but the moisture was more evenly distributed up and down the column) - and as such, it appears for now a bit iffy for storms down there; on the other-hand, it is thought this area might moisten up a bit later in the day with the peak of activity closer toward the west side.

Overall, suspect the 'better concentration' of storms with at a minimum 'anvil debris rains' at the immediate coast even will be portions of Central (East Central to eastern portions of North Central)..then along a southwest line from near Yeehaw Junction toward Ft Myers.

SUNDAY: Expect less concentration of storm coverage at this time, though upper level winds do not change, moisture availability might. The GFS showed a similar set up as today with a few variations which would be par for the course of things running along in 2-3 day 'cycles' or themes' as the larger scale synoptic scale situation across the country undergoes some subtle changes.

BEYOND: Little variation in the 'winds at the surface and aloft' forecast, with more sensible (observable) changes occurring in regard to where moisture will be ample enough. Guidance is providing varying forecasts regarding this particular variable , making an extended outlook sketchy at best.  However, there is consensus that some definite 'rather dry slots' will impede or pollute parts of Central Florida at times in the upcoming week as well as South Florida; North Florida seems to be the location where a steady increase of moisture is expected into mid and late week. 

Expect there will be days that shower/storm coverage will be significantly hampered in particular regions/areas of the state more so than others, but exactly where cannot be pre-determined at this time. The GFS shows little change, overall (as just described) into the end of the month (for the time being at least)

July 22, 2014 over the Banana River as Viewed from Cape Canaveral

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Friday, July 21, 2017

Larger Rainfall Totals - Heavy Thunderstorms Again - With Some Near Coast

Storm Clouds Loom Over Hickory Tree Road in Osceola County on Thursday.
Vivid Lightning was dead ahead at the time of image
St Cloud in Northern Osceola reported over 2.5" of rain yesterday
TODAY: Looks like a variation of yesterday's theme. KSC sounding came in at around -7.5C at 500mb and a bit cooler at 700Mb at around 7C (from yesterday). With no capping in place and little in dry air up from the surface to 500mb column would except showers to initiate easily once convective triggers are reached by noon time or so (the KSC sounding shows the convective temperature to be 89F for that area), outside of earlier smaller showers that could begin sooner.  There is already plenty of activity across SW Florida progressing slowly eastward.

Low -mid level ridge axis remains suppressed to far South Florida up toward Southern Shore of Okeechobee County today and tomorrow.

As such, steering in the mid-levels is from the WSW at about 10kts but suspect once sea breezes kick in that most storm motion will be dictated by propagation along the sea breezes as they progress inland and then along outflow boundaries / lake breeze mergers until the brew is mixed until there is one big convective mess 'somewhere' over the interior. The slightly better winds aloft today will only lead to further unpredictable storm motions across into areas that haven't already been worked over by earlier storms. The blue area in the image below is a 'guess' of where that might be.  

Biggest hazard again today will be driving in heavy rainfall and the ever present cloud to ground lightning strikes that can occur prior to heavier rainfall onset under billowing cloud tops or even outside of the storms themselves in 'clear air'.

SATURDAY-SUNDAY: For now will clump these two days together as the Song Remains the Same more or less. Only difference might be for a slight decrease in coverage, namely on Sunday, and that steering toward the immediate east coast north of Palm Beach County might increase just a bit; either that or the east coast sea breeze might get pegged closer to the coast if winds at the 925-850mb levels increase more toward 15kts which is being implied as a possibility on both the morning NAM and GFS model runs. Of the two days, Saturday looks to be the day for a Strong Storm potential once again, with decreasing coverage on Sunday.

MONDAY-WEDNESDAY: Main shift from previous thinking is that the ridge axis' remains across South Central toward South Florida for the duration into next week, even into NEXT weekend. That is to say, somewhere across South Central Florida. The pattern seems to favor more and more the east side of the state for mid-late day storms, though there is some drier air that is going to be thrown into the mix. The GFS runs a 'dry slot' across mainly Central or South Central for several days. Inevitably if this is the case, it will mean many areas will remain rain free, but on the other hand some areas along the moisture gradients across South Central and or North Central might see some vigorous updrafts evolve late in the day. 

FAR BEYOND: Just for now and then we can see how things change in the future, the GFS implies this 'drier' period for some areas will remain relatively brief, (maybe 2-4 days) as yet more moisture begins to fill in and steering remains from the WSW-SW. Granted that is too far out in time; just to throw the bait out for now..then we can see how well the models continue to bite on that prospect  in future runs.

TROPICS: Nothing in the tropical realms of concern at this time into the first week of August (at least). Even if something were to form in the Atlantic, given the upcoming pattern :  location of the ridge axis, and winds would not be welcome for a visit to the "Sunshine" State.

Heavy rainfall along SR528 near I95 on Thursday

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Sunday, July 16, 2017

Active July Pattern , Monday-Thursday

Sunday Morning - Cocoa Beach, Florida
TODAY: No changes from previous post of the other day. Pattern change from days of late slowly in progress today most notably will begin for the wee hours Monday morning as surface winds along the east coast (at least north of Palm Beach County) become light offshore (westerly) before day break as opposed to easterly or near calm . Mid-level winds also to shift from light east to west to more  from a southwest component as the mid-level ridge axis drops from Central Florida late today to near Lake Okeechobee  by tomorrow morning (though quite light).

Otherwise, for today moisture to be ample enough though some dry - pockets (like today) might well remain. 

Sea breeze converge appears will be maximized mainly North of "Dead Central" across the Interior from the Suwanee River Basin south into parts of eastern Lake County/ Western Volusia then south-southwestward  toward Central and  eastern Polk county (?) , but over all coverage appears will restricted inland except north of Ormond Beach. Better chances of seeing activity nearer the coast from St Augustine  northward.

Increased moisture was anticipated in previous post for South Florida which was the case, and as a result rain showers were set off  earlier day  ; however, at this stage it appears said activity set off outflow boundaries that 'might' have scoured out large portions off inland South Florida unless those areas can 'recover their loses'    for late day storms (which is always possible).

Not all areas in 'Orange" will see thunder or even rain today; most will be more isolated
except north of I-4 over the interior toward I-10

MONDAY: The GFS and now the NAM as well as other models have shown a curious 'thing' to occur tomorrow over the peninsula taking the form of what appears would be something like a mesoscale, perhaps heat induced surface low pressure circulation centered either near interior North Central or South Central Florida.  All in all, it looks like a thermal trough up and down the spine of the state might evolve, which in some cases results in long, prolonged rainfall eventually by the end of the day with quite a bit of cloud cover. Time will tell. Often in such cases , if this does occur, we might see more storm coverage than anticipated. 

Otherwise, it appears some storm might even come to be on the 'stronger side' from near Canaveral and North from near Orlando and east toward Off shore up toward Daytona Beach and then more toward I-95 for  North Brevard late in the day. Some activity might be able to drift offshore even from Brevard and north (eventually), bit in the form of merely light rain or thunder is too soon to say.

TUESDAY-WEDNESDAY: So far these days appear will carry on the same themes more or less. Light west to east steering, ample moisture, and sea breeze collisions point to a rather 'on the wetter side' for July pattern, but not unusual.  Biggest hazard will be lightning and expect there will be quite a bit of it. Some storms might be able to press offshore the east coast or form near it even on some days with the strongest activity mostly limited to 5 miles of more from the coast except north of I-4; however, more details are needed for refinement as these days come . 

Expect we might be hearing that on either one or both of these days that 'some storms might be strong' (due to stronger surface wind gusts near the heavier storms  later in the day). All storms will bear the hazard of lightning, however, and seeing as how some of this activity could be close to the coast the threat of cloud to ground strikes near the beaches prior to the beginning of rainfall would present a precarious situation if that is the case.

THURSDAY-NEXT WEEKEND: Storm coverage might begin to decrease overall with most activity limited to 'away from the immediate coast' ..but again too far out in time to say.  The GFS shows most activity restricted to interior Central Florida during the late day sea breeze collisions with South Florida drying out a bit.

Over all, the next week looks like it could carry on perhaps three different summer themes in groups of 2-3 days at a time as the varying ridge axis' at different levels of the atmosphere toggle for position. Outside of that, what occurs each day might be slightly dictated by remaining boundaries that lie dormant from the previous day's activity.

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Friday, July 14, 2017

Pattern Change Begins Sunday Night - But Until Then...

Sunrise Friday Morning
TODAY: Another variation of the same theme since the post-tropical wave passage of Wednesday. Easterly flow will pile up moisture along the west coast, especially near to even west of I75 in the mid-late afternoon where the strongest thunderstorms will occur. Elsewhere sufficient moisture was in place for some showers earlier today, even some thunder from South Brevard on southward, but overall the air mass especially North Brevard northward is too dry in the mid-levels to produce much than a small rain shower in the absence of any synoptic scale disturbances.

SATURDAY-SUNDAY: Not much overall change to this pattern. The GFS shows East Central Florida to be 'especially dry' all things considered, whereas South Florida might see a surge of moisture on Sunday for greater coverage there. Otherwise, the Panhandle and spots along the west coast later in the day are the better areas for thunder with the spine of the state westward all potential clients of at least a rain shower.

SUNDAY NIGHT- MONDAY: Trough of low pressure over the northeast states (aloft) will carve south enough to shift the low level ridge axis to South Central Florida ending the easterly flow of recent days ..which will result  in morning offshore winds mainly north of West Palm (though quite light)..while the mid-level ridge aloft will meander somewhere across South Central to Central Direct. Thus, expect to wake up early to a completely different scenario at sunrise than will be the case the next two more mornings.

This overall scheme of things especially sets in around Tuesday, though there are some variations of the theme  in location as to where the ridge axis will be on any given day in particular;  it's just too soon to get into the nitty-gritty details. However, the scene is set it now appears for a new pattern to be established for several consecutive days in the next coming wee.

Overall, the period of MONDAY-FRIDAY appears will be one that sea breezes from both coasts will be at hand with enough moisture to play with, especially as they begin to converge on the center of the state with some days perhaps acquiring a slight leaning tendency to favor toward the east  just a bit for rainstorm and thunderstorm coverage. No days so far show enough of an easterly push for storms to work the whole way off the coast though, so many coastal locations (meaning within 1/2 mile of the beach) could well remain dry almost this entire upcoming week. Suspect many afternoons will end with much cloud cover however from anvil debris (at least)...and some outflows from inland might work their ways to the beaches...producing at least some showers.

Must point out that as this time approaches the forecast each day will greatly be contingent upon smaller scale parameters and localized 'events' such as outflow boundaries, lake/sea breezes, as well as exactly WHEN the early day activity actually gets going. All it takes is for a cluster of earlier day activity, even before sunrise (e.g. toward the Cedar Key area on the west coast) throw a wrench in the forecast for the entire day for some areas, especially in regard to the timing of when the best chances of rain will be. In other words, this time frame could be categorized as one of the 'typical summer' patterns, of which there are several.

TROPICS: The GFS is picking up on a tropical disturbance to enter the picture (potentially) by early next week to be located over the Western Caribbean region in general and to continue moving west and north in the general direction of South Florida in days to come; however, variations to this theme are already cropping up to include a tropical storm or even low end hurricane to curve well before reaching the state. 

The thing to consider is that it by that time it is not out of the question for tropical storms to begin to play a larger role in the long term forecast as we find our way out of the ' early-mid July lull".

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Saturday, July 8, 2017

Strong to 'Isolated Pulse Severe' Storms Possible Today Parts of the Interior

July 8, 2014  Storm Moves in on The Beaches
TODAY: Ample moisture , good surface heating and mixing ratios, with precipitable water values (PW) on the KSC sounding at 1.74" and 500mb temperature a cool -8 t0 -8.5C; Tampa is at 1.81 PW with similar 500mb temperature and both reading around 8C at 700mb ,  (as too is the same case with Miami) reveals fairly uniform conditions more or less across the region (peninsular North Central to South Florida). 

The surface ridge axis is approximately across a line running east -west across Lake Okeechobee whereas the mid level ridge axis is close to Central Florida to South Central Florida. Winds at all levels are generally 10kts or less...but from the west to southwest surface up through the mid-levels mainly north of a line running from Vero Beach to Sarasota.

What this all amounts to is both sea breezes to become active and progress inland in due time (but at what rate is always a mystery) with the area around the Big Bend and SE Florida to potentially 'go off' earlier along their respective sea breeze fronts which appears to be at hand already as of 11:55AM...

As this activity sets off outflows and propagates even newer activity going toward mid afternoon the sea breezes themselves will begin to work inland..further inland from Southeast Florida north and westward...and further inland toward the east and south from NW Florida.

All this 'should' come together with accompanying moisture convergence and Deep Moisture Convergence in the presence of colder air aloft and moderate instability in the lower levels to result in perhaps some water overloading aloft leading to strong downburst winds near heavier storms. 

Given the temperature profiles aloft (which are rather cool toward the colder side as far as the summer norm is concerned) a brief spurt of hail might also occur in some isolated storms which if the cards were to fall just right in isolated areas could result in Pulse Severe.

Activity might be able to find its way all the way to the beach proper mainly from near Oak Hill (southern Volusia) and north and toward US1 or I-95 further south. Local area affects along the eastern and north eastern banks of Lake Okeechobee will not be referred to at this point as those are too localized to be worth surmising due to the large scale overall scenario at hand today, though the 'potential' is there for that  area to have some anomalies to contend with as well.  

Some light rain even might be able to be realized at the beaches proper as far south as Central Brevard eventually accompanied by some rumbles aloft? We'll just have to see.

SUNDAY: Similar scenario in the all - in - all other than that temperatures aloft might not be quite as cold; on the other hand, the immediate beaches might have a better chance at rainfall on Sunday north of Vero Beach as the surface ridge takes its most sturdy plunge southward both at the surface and up through the mid levels resulting in better (though quite weak) west to east steering.

MONDAY: Pattern begins to change. Appears air aloft might warm as winds at most levels come to be more from the south to south -southeast direction. with moisture still around there might' be showers near the beaches early on but that activity would shift to the interior in rapid fashion working into mid afternoon.

TUESDAY-THURSDAY: Moisture from the old tropical system well out in the Atlantic is forecast to approach Florida . If so, it would be rather transparent to residents; just another day at the office more or less with maybe some showers nearer the coast earlier in the day ,  with maybe Thursday being 'that day of higher chances toward the west coast late in the day, and east coast early on'    ..then Friday might be a transition day...

BEYOND (yet still?): Upper level trough might dig south along the the Appalachians providing for better storm coverage toward the east side of the state again next weekend. Yet as we approach ...

(Magic Eight-ball Time: MONDAY and BEYOND of THE NEXT WEEK: All eyes might be on the tropics with a system that has been being forecast to move across or near Cuba and perhaps poise Florida as a target within 'eye' site. Too much uncertainty at this point. Historically speaking, there has been very little tropical activity to ever hit Florida prior to the last week of July that was above tropical storm status across all recorded (officially) history.

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Tuesday, June 27, 2017

Strong Storms Possible Today Mainly North Down through East Central

Sunrise Tuesday, June 27 2017 Off the Florida East Coast
TODAY: Frontal boundary this morning remains near I-10 and most guidance implies that it will wash out today somewhere between there and the I-4 Corridor from Daytona west toward North Tampa Bay area later in the day if it can make it that far.

Morning soundings show slightly cooler air aloft across the boards both at 500mb and 700mb though the coolest from near Ormond Beach to Jax on the east coast. Steering hasn't changed much though there is about a 10mph nudge on average toward the east coast for Brevard and Indian River Counties , and a bit more of one further north. Thinking is a possible severe category storm could occur in that area around the St John's River Valley as was the case yesterday though haven't included in the graphic for 'severe' as if so, would be far too isolated to be 'forecast-able' without any real synoptic scale features of dominance at play  .

Other stronger storms along the east coast sea breeze front might occur however as far south as Indian River County closer to or just west of I-95  (and maybe even yet further south due to more of the mesoscale boundary interactions than for other reasons further north, namely better instability at the lower levels where cloud cover is not as prevalent. This activity might be able to work toward the east coast but might not retain the 'strong' caliber in the process of doing so.

Rains could dwindle Eastern Parts of North Central or Central to after dark, and even some thunder could occur then as well.

Activity might get an earlier start too near the immediate coast as the sea breeze kicks in anywhere from West Palm Beach and north, with favored areas being near Lake Okeechobee (St Lucie, Martin Counties) and the north side of the Cape (Brevard).

WEDNESDAY: High pressure  moving across the Carolinas, though not exceptionally strong will begin to take the steering aloft further south to almost nothing but with a tendency, especially later in the day for storms to drift more toward the west rather than the east.   Remnant boundary moisture could pool however across Central so even locations 'near the coast' might get a shot at some showers or thunder as the sea breeze along the east coast develops with any stronger activity waiting until later in the day further inland.

THROUGH FRIDAY: Mostly interior thunder and over toward Route 27 - I-75 appears to be where the better chance of storms will occur. Showers still possible earlier in the day some east coast locations but too early to peg down where at this stage.

FOURTH WEEKEND To THE FOURTH: Not much change in thinking . Will likely be some isolated bursts of lightning around on the fourth , mainly inland  while the east coast beaches for the most part remain rain free (?). Overall, looks very like typical July pattern coming up this weekend into early next week with the ridge axis oscillating to be located somewhere between Central to North Florida favoring the I-4 corridor and most of Southwest Florida...then also up across much of North Florida.

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