WEATHER MADE CLEAR FOR ALL TO HEAR

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

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

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

Monday, December 12, 2011

Rain Chance Highest Over the "Northeast Quadrant"

For the image of the day, the colors of yellow show where some fog is currently most prevalent, the light green where rain is most active, and the purple indicates where the best chance of rain showers should exist through the end of the day...but not limited to that area. 


TODAY: A bit hurried today, but wanted to post considering the 'what appears will be' situation per latest model runs, current very active radar, and satellite imagery. Some basics are warranted for insight as to why  we are having some rain today in an otherwise what would be a no frills day.


The remains of the old front of late last week are not apparent any more (the one that crossed on Thursday) in the wind fields, but the moisture remains after backing back north the past two days. So there we have that factor to consider (moisture). The next is that there appears to be a shallow but nonetheless readily apparent inverted trough running from the SE coast of the state NNW ward toward West of JAX. The trough comes ashore over South Central Brevard, and all of the rain showers are occurring to the east of that boundary , but...there is one more participant, the clincher. A 700mb trough (at around 10,000 ft) is passing to the north of the state and across the north half of it as well. With that trough is a more westerly wind flow as opposed to ENE-ESE winds at the surface. This trough in the mid-levels will cross the state (mostly to the north) today, not reaching south of Central Florida. Thus, rainshowers along the intersect of the low level and moist easterly component winds under the westerly component winds aloft (and likely some weak energy)...will continue to manifest before us as clouds and rain as can be seen in the above image.  The best chance for rain shower/rain chances later today per the NAM, GFS, and RUC models of 2AM are closely 'concesused' in the lavender area this afternoon, although who Really Knows. Best bet though,and willing to lay down the cards.


TUESDAY: Shower chances, although less prevalent, will oblige to shower further south from near Brevard toward Vero..or maybe toward West Palm, mainly east side. Our easterly wind component slowly backs toward ENE-NE by Wednesday, inducing some drying and ending rain chances. But until then, some showers possible tomorrow as well but not as heavy as some that are occurring today ..especially like those toward JAX at this hour. Cape Canaveral had a good shower about 45 minutes prior to this writing, long gone now. Radar is not overly illuminated toward Central but NE FLorida is a different matter. We can look though, see for yourself...



BEYOND: After Tuesday we are 'good to go' with less chance of rain. NE - ENE winds continue and could become breezy at times, but no changes really as far as our current temperature regime is concerned. In fact, not much change AT ALL up until Christmas? Can it be? I'm waiting for Jack Frost's Ax to Fall...as was the case last year...but so far he does not seem to have his sights set on a Florida Get Away any time soon. Hooray!

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Sunday, December 11, 2011

The Stage of Constant State

This image shows  the Global Forecast Model (GFS) depiction of afternoon temperature and surface wind direction and speed. The brighter toward red, the warmer the temperatures. Blue is the cold. Florida has seen no 'blue' except toward the north side of the state since last winter. On this date last year, a Freeze was on the approach. What we see in this image as far as color coded air temperature is to remain a near constant, steady state for at least a week or longer.
TODAY: Easterly wind and ample moisture from a long departed by flailing old cold front that crossed the state on Thursday is the culprit for some clouds and rain showers. High pressure to the north of the state provides the wind direction. This high will move eastward and be replaced by another as shown in the image's blue arrows. Another front will attempt to move in, but so far it appears that it will never really be able to impact Florida.


Thus, along the coast the temperatures will remain in the mid-upper 60Fs overnight with daytime highs in the mid-upper 70Fs through next week.  Moisture from the old front is being drawn west and across the state toward tne next front  approaching the state, and in doing so is bringing just enough of that moisture to provide the impetus for shower development...at almost any time..any where. Even now, as I write...I hear some rain falling outside, but it should be brief.  The GFS model implies there is a better chance than not of more of the same, especially toward the  East Central, but radar is not behaving like the model, or any of them really..however, all in all, the moisture will 'be around' from time to time until sunset.


Below is the latest radar image while it was raining. Already, it is ending. My area is circled.






TONIGHT/MOST OF TUESDAY: Again not unlike today. Although the constant prevails, the location of showers can shift, seemingly on a whim. It appears as of late morning that the moisture source will cut off by late Tuesday though..so we can take even a rain chance out of the equation through Thursday at least at that point.


BEYOND: Easterly flow continues at the same generic speed, ebbing at night. Another period of coastal stratocumulus cloud layers eventually unfolds preceding another front which might impact around or closer to Christmas. How can this be? So long, no cold front...no cold air? Very typical La Nina type pattern without an interseasonal variation such as the negative phase of the North Atlantic Oscillation (NAO) which brought cold air last year. The National Weather Service is watching the Arctic Oscillation in days to come though, or so I heard yesterday. Time has a way of revealing the future, but so far, that future is beyond the scope of reasonable assumptions.


A "Pet Tornado" in a cage at the National Weather Service spins
harmlessly, showing the magic of water vapor and motion combined  through condensation isolated to a previously established bound

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Wednesday, December 7, 2011

"Get Ready to Bundle!!!"...Floridians

Latest mid afternoon visible satellite image with hand drawn cold frontal positions. Solid blue is current front location, with dash lines showing its general location at 6 and 9 pm..give or take an hour or so.
NOW: At 3pm a cold front is careening steadily down and across the Florida Peninsula with passage already post-Tallahassee and temperatures behind the boundary close to 50F degrees accompanied by NW winds gusting toward 30mph. Not so nice for mid afternoon. Front will continue to drive SE ward during the late afternoon through mid-evening.


A word of the wises is to be prepared for surprises. But no surprise here. If heading out tonight, bring a good and trusty jacket to take a nip off the accompanying wind chill. Sweaters might not do the trick as nicely.


TODAY/TONIGHT: As noted above, "Here's Comes Da Front!". There's no turning back unfortunately, so grit your teeth a bear it. Won't be all THAT bad, but after such a prolonged warm period, and especially considering the nice afternoon today to the south of the front with temperatures near 80F or so, it's bark will be as bad as its bite within a few hours after passage along the journey to Miami. The front now appears to be over the Gainesville area as a reference point.


Front to cross Dead Central between the hours of 5:30pm - 7pm, accompanied by cloudy skies, west winds, and a slowly falling temperature. Possible sprinkles as well, but nothing significant. Post frontal passage (after dark) will yield to clearing skies and falling temperatures, especially after 8:30PM across Dead Central (sooner further north). The front will eventually slide into home plate across the Southern End of the Peninsula around 9-10:30pm, with similar sky conditions but less chance of a sprinkle or showers. Temperatures here too will fall, but the bigger temperature changes this go-around will occur over and north of the Central Lake Okeechobee area as a general line of demarcation of the coolest air.


THURSDAY: Very cool, to almost cold considering the conditions of recent days. It's all relative, and this relative will be not unlike Auntie Grezelda...sour and grumpy, but not quite bitter. Lows along the immediate ..and I mean IMMEDIATE east coast from Brevard and south near 48-51F warming to the south toward West Palm, or in another light, perhaps the coolest this area has seen this season by a smidge. 


Elsewhere, inland lows and west toward Naples will experience mid-upper 40Fs..with upper 30Fs interior North Central and even colder toward I-10 at sunrise. Winds NW around 10-18mph...with a wind chill evident no doubt.


Winds toward early afternoon already taking the turn around the bend toward the N-NNE and there ends the worst of the worst already. Not bad. I hate uninvited guests anyway. Clouds off of the Atlantic should be able to make a relatively fast return to the coast over night late on Thursday heading into Friday.


FRIDAY: East coasters can toast to morning lows already a good 10F degrees warmer. Guests leave messes...and in this event it will come in the form of a better chance of onshore trouncing low level stratocumulus clouds, especially over South Florida closer to the decaying boundary. Highs on Friday probably to remain in the mid-upper 60Fs North Central and Central, but warmer toward the lower 70Fs along the drive to West Palm and south. NNE-NE winds with possible showers late Friday and especially Saturday toward the SE Coast of the state.


SATURDAY: Continually modifying air mass (less dry and slightly warmer) through Saturday with an ENE wind. Clouds again, coastal showers/sprinkles as far north as Vero Beach.


SUNDAY/MONDAY: Showers possible mainly within 20 miles of the east coast most anywhere with temperatures returning to near normal as days of past. Warmer overnight lows especially due to extended cloud coverage, but afternoons not so warm due to the same cloud coverage. Give a little, take a littel.


BEYOND: Not much change...and a return to conditions to how it once was only yesterday and the few days before then. Next front is not on the agenda for nearly a week if not more, so no need to rush for boarding passes just yet.


Again, much cooler to apparently almost a bit cold tonight and into the first parts of Thursday...especially the north half of the state through late morning. AC, off. Jackets, On.

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Tuesday, December 6, 2011

Keeping Fingers Crossed - Winter Has No Place in Florida, So Far

For warm air frolickers in Florida, Fate is On Our Side. Recall  last winter's freeze, a faded memory of times past. This morning , I recall what was to come just one week from today at this time last year. A freeze on the beaches, and ice in the bird bath. 
http://highspeeddirt-steve.blogspot.com/2010/12/thar-she-blows-batten-hatches.html

TODAY: Another day like those of the recent. East to ESE winds, light, with some early morning mist and fog toward the northern portions of the state now in progress will lift out shortly after sunrise toward mid-morning. Highs again in the mid-upper 70Fs for the most part, with some patches of stratocumulus clouds from time to time. So far, my area has had a sprinkle or trace of rain 4 consecutive days, with a very nice December rainbow only yesterday. A rarity gift at this time of year, like a big package wrapped in a colorful bow. Considering the approach of the Christmas Holiday...a rain-bow.

I took several photos yesterday. A friend of mine in the Storm Chaser community affectionately refers to rainbows as "Peace Offerings"... The Storm Has Passed and we can now rest. The odd thing about seeing a rainbow at this time of year is where it is located in the sky because of how far south the sun is located along the horizon. The viewer must have one's sun to their back to be able to see this phenomenon, and only once the sun has reached a certain angle above the horizon (either right after sunrise or toward sunset).

TONIGHT/WEDNESDAY: Light winds after sunset, dewy with possible fog away from the coasts, but rapidly eroding after sunrise. Temperatures remain on the par.  Warmer on Wednesday as winds becomes SW during the afternoon. It has been quite a while since we have had a SW wind, and with that will be warmer highs around 80F or so under partly cloudy skies. A cold front is on the way. Mid-upper level high pressure areas moving east and away as a trough of low pressure with the attendant front replaces them toward the East Coast of the U.S., thus the wind shift and warmer air...but only for Wednesday. Enjoy.


THURSDAY: Front appears now that it will proceed through the state toward Florida, but will quickly undergo frontalysis , break down, from late Thursday and into the weekend after crossing Central shortly after sunset Wednesday evening, onward to South Florida it goes by sunrise. But not before we have a very cool morning, not unlike that of around one week ago with lows in the low 50Fs toward the east coast south of I-4, but 40Fs being the rule west of I-95 North Central and North (even colder here) and toward the west coast to the Northwest side of the Big Lake.  Fear not, the Fickle Finger of Fate (or for purposes of this post, of Cold Air Fate) will bid adieu almost as quickly as it moves in. Winds becoming NNE-ENE from Thursday afternoon and beyond. This direction is again off of the ocean waters as it has been and was last weekend, and thus, temperatures will quickly moderate back toward what we have already been experiencing the past few days by Friday.


FRIDAY-WEEKEND: Winds  having returned to their NE-ENE direction as mentioned above...could also translate to a  slightly better chance of showers somewhere along the east coast toward the interior. Until this time comes closer to 'real-time' exactly where those showers will have the best chance of manifesting will need to be determined. The key point at this conjuncture is that it does appear the chance of measurable showers as opposed to 'cloud tinkles'...will be better than it has been this week. Although, there has been some measurable amounts here and there from time to time, simply too far wide spread and erratic to warrant mention.


BEYOND: Amazingly, the GFS shows the next cold front not 3 days down the line, not 5 days down the line (the norm this time of year), nor even a week down the line. Beyond that, is anyone's guess. As noted in the top image, the GFS hardly shows much of anything other than another frontal boundary somewhere in the great beyond that has an impact similar to what that of this Thursday's   toward the 3rd week in December around the 18th or so. Go figure. This year is nothing like last year...running on track with a solid La Nina type pattern from all appearances. 

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Monday, November 28, 2011

A Prelude to Winter Begins Tonight

Mid-Morning position of Surface Cold Front and weak pre-frontal trough in the Eastern Gulf of Mexico (GOM). Both will tandem to the east, with the leading edge of   reaching the Central Interior during early to mid-afternoon, then east of I-95 toward 4pm and thereafter into the evening hours.
Wind barbs and fronts alone do not provide the mental image we need to envision what the boundaries will mean when looking outside. The vehicle to provide a future reference point is the visible satellite image. The fronts have been recreated here for reference....the green shows how the band of showers and rain are aligned with the front, so timing from this can be extrapolated eastward with time. With some daytime heating expect to see more clouds anywhere , but the will not be of much consequence until at least early afternoon toward Orlando (as a reference point), but will spread to the immediate coast after 3pm or so. Showers as well. Note the extent of cloud cover behind the cold front over the Gulf yet to come well after the front has moved east of the Florida Peninsula.

Lastly, from a broader perspective, we can observe here that the surface features are contained within a 3 dimensional entirety , consisting of this mid-level low pressure system ...as well as an upper level low (not shown here). 

Within the mid-levels toward 8500 feet overhead resides a deepening low pressure area. The 'spokes' in light blue represent for presentation purposes only of further discussion below how there will be three fronts to move across the state today through Wednesday evening. Each passage will evoke a slowly drying atmospheric moisture profile throughout the columns in the vertical, with the second and third spokes being the primary contributors within that process.  

TODAY: Wheels in the sky keep on turning, and today's is rolling across the Southern Mississippi River Valley Region and the Deep South  with more than one attendant surface low. The surface to mid level lows as shown in the above are both contained within the Mother Load..the upper atmosphere. The mid-upper levels are almost stacked overtop each other. As history tells us, that means slow progression of the ensemble as a whole, so it will be with us through the remainder of the week in various forms. Possible rain rain impacts are the first and foremost variable of interest since they  will be first realized.


SSE-S winds today at 10-20mph with gusts to 25+ perhaps over the waterways. Partly cloudy skies earlier with cloudier conditions spreading toward the east from the west coast during late morning and into the afternoon. Timing of features per close model agreement places showers/rain near  Orlando (and north) around 2-3pm and on the immediate east coast in the  5pm time frame. 


Not everyone will see showers today, especially locals who live toward the east side of the state along and south of the north side of Lake Okeechobee. Thunder is not expected, although a few rumbles are not entirely zero'd out ...just highly unlikely.  The atmosphere is neutral enough in the instability parameter such that it would not be an issue. 


The main impacts are cloudy skies, breezy, and showers from late afternoon through 8pm or so in the area north of the less likely area to the south. Winds will become SW-W-WNW shortly before, during, and after passage of the two boundaries...which will clear the entire state after midnight ..apparently most definite prior to sunrise all locations.


TUESDAY: Mainly West winds at 10-18mph G 22. Partly cloudy after a morning low in the lower 60Fs far east to mid-50Fs interior. Cooler tomorrow with highs in the upper 60Fs to lower 70Fs South Florida. In all cases, cooler north of I-4.


WEDNESDAY: The second boundary/front will be moving through late in the day after another cool start in the 50Fs and low/mid 60Fs. This will be the first influx of truly (noticeably) drier air. Passage of this boundary will take the winds toward a definitive NW direction over night with falling temperatures to a greater degree as the drier air moves in.


THURSDAY: The second boundary now  having cleared the state with much drier air (lower dew points). Lows in the low 50Fs to upper 40Fs many areas except the far north (colder), and south (warmer). Very cool Thursday afternoon with highs in the mid-upper 60Fs with much clearer skies by now if not sooner on Wednesday. Hoping for 70Fs though, which is not out of the question.


FRIDAY: Round -the- wheel goes as it lifts toward the eastern Great lakes. The final front will have to approach from a much more northerly directory, with N-NNE winds to follow during the afternoon. Timing will have to be re-adjusted in regard to exactly when this will occur. Some clouds associated with this feature, followed by a warming trend through the weekend to seasonal norms.  

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Sunday, November 27, 2011

Fairwell Warm Weather Friend...Parting is not Sweet Sorrow

5PM EST Rapid Update Cycle (RUC) model depiction of surface cold front for today in its last model run
This front will approach from the west with a fairly rare but steadfast north/south orientation, making only slow progress into most of Monday as the supporting mid-level low only recently becoming apparent forms in the yellow area for descriptive purposes.  In Green is where the best chance of measurable rainfall with the front itself seems the most probable as of this time, with the area in orange a thunderstorm area to be honed in on for future reference but in no way definitive at this stake.   

TODAY THROUGH NOON MONDAY: Very little change from what we are seeing over Central and South Florida as winds continue from the ESE-SE at 10-20mph with higher gusts at points in time almost anywhere depending on the daytime heating and any manifestation of nearby low topped sprinkling showers which dictate near by conditions (a few stronger gusts/slightly cooler due to cloud cover) - of which will be few and far between.  


Animation of early afternoon visible satellite imagery indicates that most areas other than toward NE and SE Florida will see more sun than clouds, although this could change come   lower sun angle time of day , but not of significant due cause. Otherwise, temperatures running in the 70Fs with some lower 80Fs away from the east coast north of Ft. Pierce and toward the west of I-95.


By noon Monday, the cold front should be approaching if not nearly on the west coast of Florida, with winds becoming more southerly at 10-20mph with similar if not slightly warmer highs along  a low" 80Fs more common" thread. Showers and possible thunder over the Panhandle toward Tampa with time, possibly as far south as Sarasota and eventually Punta Gorda west coast, with a few showers possible east side south of Daytona as the afternoon wears on, but those would not be related to the approaching boundary on the west side.


MONDAY NIGHT: Cold front, due to its orientation as shown above, will clear from west to east   along a common longitude, passing  or clearing for example I-95 within nearly the same hour from Daytona Beach to Miami..which per the latest NAM, GFS, and ECMWF (yes, the models have finally reached near mutual concession to agree)...around 7:30-9PM Monday evening. Best rain chances as indicated above as well, but most anywhere not shown here could receive showers as well. The least likely area appears to be SE Florida ...in the rain realm...but we can't know definitively until some rough spots in information get ironed out. 


TUESDAY-THURSDAY: To skip back to the previous paragraph, it could be that the precipitation to occur from west to east Monday afternoon through mid evening will actually be along 'PRE'-frontal boundary, with the true front yet to cross the state a day later. In either case, it does not seem to have an effect on sensible weather, only wind direction. 


West Winds after the trough presses to the east of one's location with rain chances quickly dwindling and over by sunrise Tuesday. Much cooler air could come in two phases but the sum total of both would be mainly to re-inforce the initial surge neither taking away from, or adding to, the numbers. 


Lows interior to south Florida in the mid-upper 40Fs, and upper 40Fs to just a tick above 50F far east side. Colder all areas north of I-4. Afternoon highs warmer than the cold previously  feared (but not surprised of this) on all days into the mid-upper 60Fs to low 70Fs south with westerly winds ticking clockwise toward NW on Thursday with time.


FRIDAY/BEYOND: Preliminary. Somewhere in the scheme of things heading toward next weekend another front will be making an appearance. Ironically, this cold front could come in the back door, from the North to NNE as opposed to our incomer from the west on Monday. Ironic because it is behind this front that conditions actually warm due to the wind becoming N-NNE-NE behind it. More implicitly, cold air will be modified as it blows across warmer ocean waters with a net result of a return to the old "stratocumulus clouds, warmer overnight coastal lows, and comfortable afternoons in the 70Fs with the ever-present chance of sprinkles of maybe showers somewhere along the line"...too soon to say.


CONCLUDING THIS POST: It continues to look like it will be much cooler to almost cold Tuesday through at least Thursday morning, and probably Friday's as well...with temperatures running below normal. This expectation in and of itself would not be of much perceived impact t'were it mid-winter, but we have been running above normal for quite a while, so these colder temperatures brought forth with a period of some winds in the 10-20+ mph will add the wind chill factor in. Cannot recall  the last time that was even of concern. Looks like the A/C can go for a while...but what of the heat? Individual preference , "You Be The Judge".    

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Friday, November 25, 2011

Black Friday Forecast Frills - Bleak or Best Buy?

For image's sake, this is what the clouds over the state look like from above this afternoon, compliments of satellites above which relay the information down to planet bound denizens  

TODAY Through SATURDAY: High pressure just to the north of the state is slowly sliding east with Florida in the return easterlies behind its clockwise circulation. Moisture is just deep enough to generate the clouds as seen here and if you look outside, there as well (in most cases). Otherwise, winds from the East to ESE at 10-20mph with some higher gusts and highs in the mid-upper70Fs are the prevailing modus operandi through Saturday, although it could be  a few degrees warmer (especially than those of today) toward the Panhandle.  Shower chances are not zero, but even if they can manifest, they will be so light as to be considered 'no impact sensible'. 


SUNDAY-TUESDAY:  Sunday's winds become  SE-SSE (if not South), with temperatures running into the upper 70Fs - lower 80Fs (most likely). From there begins the dilemma. So, rather than provide a detailed  and quite laborious task of synoptic scale differences between each model at various atmospheric levels, we can look at why this is the case at hand in the first place. This can be best performed by observing a few discrepancies between the weather models used to forecast temperature, rain, and wind based on the mathematical equations employed by each without going into detail.


ASSUMPTION (S): It appears that there could be some interseasonal variations being detected or in process but which have not yet come to fruition. Most readers will have heard of La Nina which seems to be running right about normal (in many years it is not present, or the counterpart Le Nino is in force).  That is a factor to consider. Then consider this possibility: the Madden-Julian Oscillation, affectionally referred to as MJO (as opposed to having a MOJO). Yet still, perhaps the North Atlantic Oscillaion (NAO) might also be scheming an attack to ruffle  the forecast's feathers. Point is, given the time of year , climactic winter on the very near approach and variations within this time a near given initially, combined with those additive factors,  each model by all appearances seems to be weighing one of more of those variants into their equations..but providing astoundingly dissimilar results.  Examples:


The Global Forecast System (GFS) Model: Front to cross the state overnight Sunday night, accompanied by rain showers for at least the north half of the state, followed by a significant cold down. Lows in the upper 30Fs (north) through the mid-40Fs south by Monday/Tuesday time frame, with highs never breaching 60F most areas. The GFS of this morning shows these very cool to near cold (as well as very dry) Floridian conditions to prevail through early Wednesday . Well below normal. The next front arrives after perhaps 18-24 hours of slight warming before yet another re-enforcing front comes through dry...and more cold air of similar consequence...a long cold week by standards of the past 8 months.


The European ECMWF model on the other hand from last night does not have the front going through until sometime toward late Tuesday or early Wednesday. Additionally, it forms a surface low in the eastern Gulf of Mexico just off Cedar Key...with much more time for southerly flow to prevail prior to frontal passage. That would allow for not only deeper moisture to be in place prior to passage, but also create a set up much more favorable for thunderstorms as well (perhaps severe). Frontal passage was generally indicated sometime Wednesday at the latest per this model's bidding.


The NoGAPS and Canadian Models fall somewhere in between the two, with the CMC (Canadian) coming closer to shaking hands in agreement with the Europeans. Then again, the Navy NOGAPS model sides with the GFS,  not exactly...close, but slower.


Eventually, something resembling a model treaty will evolve , likely (or hopefully) by Saturday evening. By the time we reach Sunday morning...it should be completing signature, but we will have the opportunities to see in each and every subsequent model run of each player just exactly what the TREND is.


If only it was as easy as going to Best Buy to know right now.  The common remark made by National Weather Forecast offices in these cases sums it up neatly and simply,  "Stay Tuned" (the old fall back, "A word of the wises, be prepared for surprises" could aptly work as a second opinion of opinions.) Or as Confucius Say, "Forecast Model Not For Sale, Look at Sky and Figure out yourself".

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Wednesday, November 23, 2011

Several Weather Changes Next 7 Days - Gentle Intro to Winter

In blue are generalized cool front locations as noted in the time-phased image shown. Coverage of showers at any one time will not be extensive and will be mostly associated with the front itself upon approach and passage

TODAY: Cool front across the Panhandle to make slow progress into Central Florida from early afternoon through sunset. A prefrontal trough associated with the radar echoes shown in the image above  is damping out, as such are the showers. Increasing cloud coverage to spread across Central (some already in place), with breaks in the clouds to allow highs today to reach the upper 70Fs to around 80F or so. Warmest S. Florida by a few degrees , not significantly so. Using a combination of morning RUC and NAM, the RUC appears a little fast. Likewise, perhaps the NAM is too slow. In combination, it appears another diurnal pre-frontal trough will form across the CDL (Central Diving Line) Zone this afternoon with daytime heating and hold tight, allowing the cold front itself to play 'catch-up". This will for whatever can be mustered up with cloud breaks as the front progresses only slowly SE ward from North Florida to provide a focus for rain to happen chance.


Suspect much of North Central will be stabilized/hampered by greater cloud coverage from the pre-existing trough that is moving out this morning, and so rain there should be limited to sprinkles and a few spits. Further south toward Dead CDL, cloud coverage will be less extensive. West winds all day, possibly becoming WNW behind a pre-frontal trough North Central (and prior to the actual front).  Winds from surface to well aloft will be mostly unidirectional (from the same direction) with height, and instability will be severely hampered by cloud cover and be mostly surface based due to mulit-layered clouds. Thus, the better chances of rain today/tonight appears will occur along and south of the secondary pre-frontal trough from Brevard County, possibly part of Orange/Seminole and south toward Miami (with time overnight as the front moves in that direction).  If there is to be any thunder at all, it should be elevated type harboring mostly incloud or cloud to cloud lightning, but not feeling very strong on any of said activity. If so, Brevard to Martin County within 20 miles of the coast.


The image above shows general locations will the front should be today through early Thursday. It currently appears that a "diurnal frontal stall cycle' will occur near I-4 to Dead Central during the mid-late afternoon, with no clear delineation as to exactly where the front is located until after dark once that cycle is complete. From that aspect, the front will be free to plow through toward the Straits by sunrise if not before.  Best chance of showers appears to be when convergence/low level winds sync with the time phased diurnal cycle combined with the fronts location near Central as high pressure builds east across the Deep South region toward Georgia. This puts the best covergence/abrupt wind shift on the east side of the state toward Southern Volusia / Brevard region around 8pm as the front will be close to there.  All in all, most people today will not receive rain under partly to mostly cloudy skies and west to West Southwest winds around 10-18mph this afternoon. At some points (or points), skies will be cloudy, but for residents across South Central and South that will occur after sunset.


TONIGHT/THANKSGIVING DAY: Front to press south and be followed by a NNE-NE wind by sunrise most locations (after veering overnight from the NW).  Sunrise should yield a Thanksgiving Day with lows in the lower 60Fs and 50Fs north Florida, warming to the mid-upper 60Fs toward Central and upper 60Fs to lower 70Fs South Central to South. Cool and breezy day with winds from the NE at 15-22mph, gusts toward 28mph. Looks like possible Lake Wind Advisory conditions and Small Craft Advisories might be required. Stratocumulus clouds, but not extensive to follow by mid-late afternoon. Not all that much warming during the day, perhaps up it about 5 degrees from morning lows as already modified cool air advection sweeps across the state from off the Atlantic.  In short, breezy and cool with some clouds. For Friday, NAM continues with bringing in rain showers most of the east coast by morning or shortly thereafter with a nearly saturated atmosphere from the surface to 5000 ft. This seems like 'overplay", and if even so, having a hard time rationalizing anything but more clouds as opposed to showers.


BEYOND: Next front to impact the state beginning Sunday through Monday. Rainfall appears will be more likely most areas with this front, only 4 days later. But hold on, yet another front could follow in due time within another 3-4 days if not less. This next front could manifest anything from widespread showers to isolated thunder, maybe even severe. If so (the latter), it would most likely be for the North Half of the state. Good wind shear but meager  thermal instability being the ever present liability as we approach the last quarter of the year, aka Winter.


As noted yesterday, much cooler from Tuesday and through the first week of December, except maybe for a day or two before the second front comes in to re-enforce Winter's Urgent Calling Card. So far, it doesn't appear it will be extremely cold, just very cool to almost cold (in the mornings) for a prolonged period. Slow and easy...  for easier adjustment without a profound shock to the system.

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Tuesday, November 22, 2011

Are "Winter Like" Conditions Systematically Oozing In Through Next Week?

Today's Broad, Albeit Generous, Brush of where precipitation could fall. The best chances appear to be toward the interior north late afternoon through mid-evening. Sprinkles could occur within the yellows. Nothing beats color coded weather. Wish it was that simple.

TODAY: High pressure off SE Georgia and the Carolinas eventually elongates eastward into the Atlantic to be replaced by ESE-SE flow through late evening, becoming SSW-SW prior to sunrise Wednesday. A potent cold front related complex of three dimensional ferocity will rage across the entire Deep South today into the evening, with possible supercell (rotating) thunderstorms ahead of and imbedded within a Quasi-Linear (as opposed to completely linear) Squall line could   be on the menu of this smorgasbord containing severe category wind gusts as well as hail in association with the cold front which will approach Florida tomorrow.


Meanwhile back on the farm, looks like a good day for bailing hay with summer like clouds across the state, with the greatest concentration of clouds  near the east coast of South Central and north, eventually to make a showing all interiors by early afternoon. A few sprinkles near the coast from Brevard and north (South of I-4) with a better chance of showers near and north of I-4 to possibly St. Augustine by late day. Although Central is in sufficient moisture for showers or nearly so, much of it is being advected out of the area before showers can form. Central is the Source region for regions further north where better convergence can occur along a line running from Tampa, Ocala, toward Daytona and north. Best convergence should be over the interior late in the day through mid evening  in  proximity of that  green box traced out in the image above.   


TONIGHT: Cold front approaches the western Panhandle. Wind overnight becomes SW toward midnight and beyond. Partly cloudy in spots, becoming almost cloudy north. Best chances for fog tonight seem to be interior South Central (South of Orlando) and all of South Florida where winds will be lighter. Coolest temperatures will be away from any clouds which should be South Central, with lows in the lower 60Fs. Warmer further north under the increasing cloud blanket, and further South per common logic.


WEDNESDAY: Main point to observe is that the atmospheric moisture ribbon associated with the front is quite broad. Moisture both precedes and follows the boundary, so clouds could be on the increase from north to south during the late morning and through the afternoon. Winds from the WSW-SW all day, but cloud cover comes with the moisture, so afternoon highs across Central and North Central will unlikely be as warm as they could be otherwise, but South Florida (where the fog will be earlier), has a better bet of the warmest pockets. Highs most areas reach the lower 80Fs south of I-4 ..with some mid-80Fs South Florida before the better cloud cover can move in , which will post-peak heating anyway. 


Cloud cover seems a given to various degrees all North and Central, with the morning NAM showing a better chances of at least a sprinkle both before and after frontal passage. For now riding with the GFS, which implies almost solely clouds, with possible sprinkles/a shower along the immediate east coast East of I-95 as far south as Melbourne. The Cold front ETA for the CDL (Central Dividing Line) is within an hour or two of sunset (most likely after)...progressing toward Miami/Dade toward sunrise, Thanksgiving Day.


Winds behind the front shift to WNW, then NW, then N, then NNE within 11-14 hours after passage, which equates to NNE winds by the time the morning grapefruit and AllBran is being served Central, working toward South Florida by late morning toward Noon Time..


THANKS-N-GIVING DAY: NE-ENE winds ALQDS (All quadrants) at 15-22mph during the day, with some gusts in the upper 20s. Looks like a Small craft advisory type of day, with plentiful stratocumulus clouds working in by early-mid afternoon as well once the depth and longevity of these winds persists down and east of the Gulf Stream waters offshore. Showers unlikely, but it could look like there will be rain from time to time as the sun sets. 






OVERNIGHT-FRIDAY: Continued winds of similar direction and speeds, with more clouds as well. Overnight lows in mid-upper 60Fs to near 70F+ at the coast, especially South/South Central. The NAM is showing incoming showers Thanksgiving Night through Friday east coast. Certainly, upon inspection of the forecast soundings moisture is good, however limited to a shallow 5000 ft,...which wouldn't justify anything beyond a wind blown sprinkle, especially since there is no convective inhibition...allowing any instability to escape into the wild gray yonder. Time will tell.


BEYOND: Per the header in the post this morning, and as previously pointed toward, another front is on the horizon for late Sunday into Monday, just 4 days later...this front could be the harbinger or foreboding of a trend toward climactic winter. In other words, there's ALMOST no turning back now.  The next front will take our overnight lows/daytime highs down a good 8-12 degrees / 5-8 degrees respectively (which is for the first few days of December). 


If the latest GFS trend stands fast, there is yet another front following suit 4-5 days later; thus, once again breaking the old  "One Front per Week" rule of the past month and a-half. Two fronts in a row, 5 days apart is more 'winter like', not allowing for much recovery in the temperatures between them.


This by now third front  being referred to toward the end of the first week of December bears watching....from the active weather prospect.    

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Monday, November 21, 2011

Thanksgiving Weekend Round One- Showers Today

IMAGE: Mid Morning surface temperatures are shown. Note the 70F degree isotherm. It is along and south of that line, in general, that the best chance of showers should exist today. The area in light blue is where measurable rainfall totals appears to be  possible, but not solely inclusive. However, even those chances look pretty slim, with coverage likely being restricted to a few locations (again, if any) by early afternoon through dusk.

TODAY: Surface high pressure just off/near the coast of Georgia/South Carolina and in the mid-levels almost directly over the state of Florida today is making for weak steering currents with low to mid- topped showers  moving from the east to ESE toward the west to WNW. All model guidance this hour is showing for some pretty good rainfall across the Southern Half of the state..or rather..some moderate rainfall in showers  with truly measurable amounts without having to bat an eyelash in doubt. 


However, that has been the case in the short term models for the past few days with not nearly the coverage depicted..nor where it was expected. Given the trends of morning radar/satellite loops I suspect they are again over-playing today's wet spots so taking the broad brush approach as shown in the above image for favorable coverage areas. Outside of those rain chances, the winds have noticeably dropped off, which sure is nice change.


 Net result will be a warmer day along the east coast and likely interior outside of the clouded over areas, with highs in the low 80Fs and possibly some mid-80Fs interior areas South 1/2 of state. Low 80Fs north.


TONIGHT/TUESDAY/EARLY WEDNESDAY: Very light wind and rain chances ending as the sun approaches the west horizon with nightfall. Near calm wind tonight with a shallow low level inversion under mostly clear skies should be able to set up for respectable 'fog spots' almost anywhere with good radiational cooling , especially the north half of the state.


Tuesday looks to be a dry one with comfortable temperatures running again close to those of today, but with warmer temps running the across the entire state by afternoon. Light winds not worth mention.


Wednesday again has a chance of early morning fog/mist, especially South. This was noted as a possibility nearly 5 days ago if not more and continues to be the case. Very cool morning for east coasters with a west wind (very light). This will mean "no sea breeze, land breeze instead" and thus no warm ocean water air being pushed ashore. Lows in the lower-mid 60Fs as opposed to the lower 70Fs that were felt along the east coast of Brevard and South this morning. Lower 60Fs seems to be the prevalent mode in the morning (widespread), but warming into the mid-80Fs over a broad expanse as a cold front will be moving across the Panhandle early in the day with some showers/thunder possible there. There is a front on the approach, and temperatures Wednesday morning might actually be cooler AHEAD of the front than behind the front (in the mornings).


THANKSGIVING EVE/THANKSGIVING: Cold front timing of course is always a player this time of year in the wind/rain/temperature fields (i.e., weather).  Like the previous front, this one appears to go through mainly dry for  Central and maybe even North Central this go around..and mainly overnight with some clouds. Front will be moving across North Central  after midnight toward sunrise and should clear the CDL (Central Dividing Line) close to sunrise, followed by NW winds gradually veering to north to NNE by day's end. The boundary could be playing through the South Half of the state most of Thanksgiving Day, with a better chance of showers along a line from Vero Beach - Sarasota and south. Comfortable temperatures even behind the front but becoming breezy toward the east side by mid-late afternoon as a wind surge moves in. Chances are this will be accompanied by cloud cover. All in all, averaged over the years, this looks to be a very "average Thanksgiving" for most of the state other than the south half. Previous Thanksgivings have varied to very very warm to Severe Weather, but mostly are uneventful.   


This front looks like it will have very little impact on the temperature fields worth mention. Temperatures return to those experienced the past few days (with today - Wednesday being warmer), with similar wind as well, stronger for a day or two from the NE-ENE-E after frontal passage.


EXTENDED THANKSGIVING WEEKEND: Looks similar to the  previous post of a few days ago: Another front will break the "one front a week rule" of the past month or so, with an arrival at the End of Thanksgiving Day weekend or roughly 4 days later. It is possible this low pressure system/front could entrain moisture from the tropical Pacific, with a steadfast surface to mid-level low to develop over the area around North Georgia with time. Timing would place the boundary through late Sunday..and it's not pretty.


As noted previously, this second evil twin front could be an introduction to the formal onset of Florida Winter almost right on cue with December 1 except it would be around the 28th of November. Overnight lows do not look terribly cold; it is the amount of dry air and very cool afternoon highs that will be the bigger impact if all goes according to "Plan". 


The front also appears to have a better potential to be a 'wet' one...with possibly preliminary rain/showers impacts as well as opposed to only with the front proper.  All in all, experience says that once a pattern is broken this time of year it could be a longer duration break from previous experiences in the same period/time frame. Thus, overnight low and day time highs might never fully recover to those we've had the past week or so.  This boundary could also lower the water temperatures along the near shore Atlantic which would mean that the next time we have onshore winds they will be cooler from previous periods of long duration easterlies. 


Still too early at this stage of the game to set the extended  down in concrete...  all could change in a flash.  At least we have a head's up, not to be worse for wear.

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Thursday, November 17, 2011

Dis-solving/De-Volving Frontal Boundary Making for Low Confidence Forecast

Radar Shortly after sunrise shows band of convection with lightning/thunder involved across North Central/West Central along a pre-frontal trough, with the actual cold front lagging by a good 3-6 hours.
CURRENTLY AT POSTING TIME 845AM EST: Low clouds/ceilings and some fog exist across the peninsula from along the leading edge of the pre-frontal trough (noted by the rain/thunder on radar above) and South, with the densest fog being officially report near West Palm, Winter Haven, and Ft. Myers. Elsewhere, skies vary from cloudy to nearly clear. ..with some sprinkles near the Keys and showers off shore South and South Central along the west edge of the Gulf Stream and/or the western periphery of high pressure pushing offshore the East Coast in the lower portions of the mid-levels.


Yesterday, a record high was recorded at JAX, and a record warm morning  low temperature was measured at Melbourne (72F). 


TODAY: Low confidence forecast in the rain department today. Based on latest RUC and very early morning GFS/NAM, what is left of the pre-frontal trough will press toward a North Brevard to Sarasota line by noon or shortly there-after. The actual cold front remains several hours behind though. During the course of the later morning to early-mid afternoon expect that some diurnal effects could allow a bit of a 'catch up game' to commence between those two features, although for the most part the boundary denoting the prefrontal trough never really clears much further south than the CDL (Central Dividing Line) tilted toward Sarastoa to Titusville/Sebastian (somewhere in there).


 Cloud cover will also be tricky since the rain/thunder forecast (particularly from Central portions) will be at least partially reliant on 'lack thereof clouds' to destabilize the atmosphere. Additionally, during the course of the day Deep Layer Shear (through all portions of the atmosphere) and increasingly weaker lapse rates (temperatures not decreasing as much with height) will add to the uncertainty on how unstable the atmosphere will become through a deep enough layer to generate thunder. 


As can be seen on the earliest available visible satellite image, high clouds could impact Central late morning through afternoon. Whether those will erode and/or press off more toward the NE is uncertain, but so far that does not look to be the case.
In this satellite presentation, the band of clouds/rain can be seen across the North Central Peninsula in relation to the cold front. It does not appear that they will be eroding, and could begin to blanket Central Florida as far South as Melbourne by late morning, however, some of what is near East Central in this image is actually only  low clouds / fog, which will dissipate by mid-morning.
     Time-phasing just exactly 'when the front will be where' becomes more difficult when looking through various levels of the atmosphere. High pressure is also building ENE from the SW Gulf, so the upper level winds could become WNW-NW prior to the surface wind shift related to the front proper. 


When all is said and done, and to keep it at a less confusing level for reading purposes, Dead Central will be within the confounds of the frontal boundary at some level or another (surface to 5000 ft) from where the pre-frontal boundary is now located and south toward a Vero-Charlotte (west coast) until late afternoon. South Florida might never see a solid SW wind ahead of the front, but could still see showers and maybe even some thunder either way though.

EARLY MORNING FIRST BEST "WILD  GUESS" for rain and thunder chances. Do not expect a broad coverage at any one time, with rains confined to either Central (especially near the east side) and South of Lake Okeechobee after 1pm and beyond. Dashed orange indicates where thunder could occur, but as noted above, at this time of day (9AM) it's as clear as Mississippi Mud just exactly where thunder is most likely to occur.
IN SUMMARY FOR TODAY: I'd anticipate that it will become much more clear where thunder/showers could or will occur by 11AM -1PM once diurnal heating has commenced and the cloud pattern trend becomes apparent. Latest RUC/NAM and the GFS (which has been consistent) that there will be a frontal 'hang-up of sorts" during the diurnal cycle along a tilted CDL as noted previously (above). Showers/thunder could occur here near that line from just after noon time toward 4pm concurrent with other showers further south of Lake Okeechobee (mostly over the Everglades)..SW of Lake Okeechobee.  Chances are, that once the sun gets within about 30 degrees of the horizon there will be a rapid transition with the frontal boundary re-emerging on paper over Southern Dade county (around 7pm)..after which point it progresses toward Central Cuba by Friday afternoon.


LATER TODAY/TONIGHT: Rain chances end for those locations currently receiving rain now by late morning, with the better chance toward Southern Volusia to Southern Tampa Bay and south across the Space Coast / Orlando. (as noted)...as well as South Florida mainly near the East Coast and SW of Lake Okeechobee from 1pm and beyond.


Winds today will be mostly SW and become nearly west behind the decaying prefrontal trough. Frontal passage will be non-eventful with a wind shift to WNW eventually NW and then North, working down the coast from Central to South Florida between 6pm to mid-evening, and increase in speed as winds become Northerly and eventually NNE-NE overnight to early morning in the 20-30mph range, especially near the coast.


TEMPERATURES: As of this morning, temperatures behind the front are in the mid-upper 50Fs in the western Panhandle, and even still in the 60Fs behind the front after immediate passage. 70Fs remain toward JAX and South. Post frontal temperatures late tonight through Friday will resolve with lows mainly in the low-mid 60Fs from Ormond and South, and rising toward the mid-upper 60Fs Space Coast and low 70Fs Treasure Coast and south. Afternoon highs ranging from the 60Fs NE Florida toward 70F mid-lower Space Coast and above Treasure and south. Ongoing NE-ENE winds of 12-25mph off the ocean (the quick recovery in onshore winds) will preclude significant low level atmospheric drying, so this day could also be accompanied by scattered to broken stratocumulus clouds and rain showers/sprinkles (mainly South Central/South Florida) providing for further reason to temper down afternoon highs as well as preventing overnight lows Friday night from falling little if at all South of DAB after sunset Friday night.


WEEKEND: GFS continues with the trend of high pressure rolling quickly from Western Kansas eastward to Arkansas/Tennessee and off the Carolinas by Later Saturday. Winds become Easterly and gradually decrease on Saturday afternnon . Eventually, winds above the deck become almost ESE and rotate a portion of the mid-level front back north toward South Central. Rain showers and continued cloud cover at times during this transition (especially Sunday) could result in sprinkles and measurable but small amounts over South Florida and Coastal South Central, with lesser amounts to barely a trace north to JAX...although sprinkles could occur toward JAX as early as Later Friday as well.


MONDAY: By Monday it all becomes a moot point as winds decrease and high pressure in the mid levels builds directly over the state ahead of the next large upper level trough over the Western US. Still though, there could be some annoying Stratocu almost anywhere through Monday/Tuesday, with a re-emergence of the early morning/overnight low cloud/fog issue in extended forecasts under the high pressure since low level moisture remains, especially Tuesday/Wednesday.


WEDNESDAY/THANKSGIVING: As noted in previous posts, we've been essentially on a "one front per week" schedule/cycle over the past month, and the next front enters the picture unfalteringly (unfaultering?) so per guidelines. This has been on the platter for several model runs, but just exactly what transformation /weather conditions this front will entail is only slowly coming to light. The trend has been, or appears to be heading toward, a cloudy and possibly more wet Thanksgiving and into the weekend..with comfortable temperatures: aka - the round the clock 70Fs, with some lower 80Fs scattered asunder.


However, on the other hand, the GFS is screaming "PATTERN CHANGE" as well. This will be a change in the hemispheric (northern) realm more than likely, with the next front forecast to come in quickly only 4 days later as opposed to 7. This will be very close to the last day of the month, eerily on the cusp of calendar/meteorological winter, December 1. Could be a big drying trend in the future with another overall lowering in morning lows and afternoon highs the majority of the time, or rather, toward norms. In short, winter could be knocking on our chamber doors...Get Back, Jack!...(need we say, frost?).  

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Wednesday, November 16, 2011

Near Record High Temperatures, Small Shower Chance Late Day/Evening

TODAY'S HIGHLIGHTS features surface to mid-level ridge across South Central which will drop only slightly south during the day. Satellite image at sunrise reveals areas of either very low ceilings or fog. Deepest moisture resides over the East Central Gulf and along a cold front approaching the Panhandle later tonight (where some thunder could occur)

RECAP: Showers formed yesterday in the proscribed zone in the prior two day's of posts from Southern Polk County and across most all of Central Osceola County toward dark, eventually dying off toward 10pm as they reached the Titusville area. There has again been some fog reports, but not with the greater coverage of Monday morning. Lower clouds seemed to be the more prevalent mode, as temperatures in many areas statewide were mostly in the low-upper 70Fs, warmest along the SE Coast near the warmer Gulf Stream waters from West Palm and South where winds remained off the Atlantic overnight.


TODAY: Not all the much different from yesterday, but there are some minor changes, mostly in the strengthening S-SSW-SW gradient low level wind flow north of the ridge axis shown above as the frontal boundary and supporting mid-level trough approaches from the Deep South region, positively tilted toward the Ohio Valley. This can best be seen at the 2000 ft level, as forcing and wind fields at the surface are weak and less discernible for presentation purposes.

Latest RUC roughly shows the front to be located at 2000 ft. above ground as shown, with ridging across South and South Central Florida along the high pressure ridge axis emanating from east of Bermuda. Both of those ridges will drop generally another 50 miles south during the day, and place Central Florida from generally 20 miles south of the CDL (Central Diving Line) and north in stronger SW-WSW flow from 2000 ft and up by mid-late afternoon.   Recall from the first image, deeper (but not tremendous) moisture is over the East Central Gulf. This moisture will circulate east and north during the day into those locations along and north of the ridge axis, or roughly from  Melbourne Beach to Tampa Bay and north by sunset. Dry air is being advected into South Florida north of Cuba. 
 TODAY: Frontal boundary to enter the Panhandle by tonight. Winds today over North Central and North Florida from SW-WSW becoming more southerly toward South Central and SE South Florida.


The RUC model indicates the best moisture will rotate in later this afternoon toward Brooksville and exit the east side of the state very close to a track following along I-4, where showers could occur. 


On the other hand, the latest NAM is depicting a scenario similar to what occurred late yesterday/last night, only about 20 miles further south and east. This would place the area of Central Osceola County again in the better rain chance as well as the area very close to 528/Port Canaveral/Cocoa Beach/as far south as Melbourne Beach for a rain chance between 6pm -10pm as opposed to the more northern area of interest of the RUC. Either one is game, but at this time resting on the NAM which has not been the favored model for quite some time (since summer). However, it seems to have been doing fairly well during the first 18 hour time frame and always one or two steps ahead of the RUC, and did well yesterday.  


These showers could actually emanate/result from a weak Lake Okeechobee Shadow affect (there was one visible yesterday), which would provide the moisture convergence necessary to result in some lower topped showers. I saw one lightning strike on Lightning Tracker last night toward Southern Polk County, but for now will leave it out (which could change) for today. CAPE (instability) appears that it will be even stronger today, but lapse rates on the other hand look weaker which will 'negate CAPE'.   See first image above for those areas highlighted in lime green.


TEMPERATURES: Otherwise, outside of the rain chance it could be pleasantly warm today under partly cloudy skies. Highs in the mid-80Fs interior South and Central Florida. With clouds starting the day in many locations, some records could be toyed with toward the west side of Lake Okeechobee running along a diagonal toward Interior Volusia under to condition that there is good spatial separation in the clouds during the peak sun angle hours. The coolest areas today will be downwind of any water body which would mean the areas east of US1, to the north and northeast of larger inland lakes, and along the north shores of Lake Okeechobee.


TONIGHT: Frontal boundary will be working across the Panhandle. Best chance for some repeat fog conditions appears to be further south tonight, essentially almost anywhere near and south of Lake Okeechobee. Surface winds and especially just above the ground tonight should be too strong for fog north of The Lake  as the frontal boundary approaches and the pressure gradient between that feature and high pressure over South Florida remains firmly in place over that region, resulting in much lighter winds at all levels over South Florida.


THURSDAY: Front will be working from NNW-SSE during the day. Latest guidance generally agrees that the front will work past Gainesville toward I-4 between 11AM -1pm, and will be accompanied by a good 6 hour window of most cloudy/cloudy skies and perhaps some sprinkles. Instability will be able to build further south of the I-4 during the afternoon further from the cloud cover,  with winds from the SW-WSW resulting in highs in the lower to maybe mid-80Fs depending on how soon the leading edge of cloud cover moves in. Although there is a chance of less than measurable rain along the front, the better chance for measurable rain will be toward the East Side of the state South of I-4 to north of Sebastian Inlet from 2-8pm. Frontal passage across the CDL (Central Dividing Line) should be close to 6-7pm time frame. The front then washes out at the surface south of the Beachline Zone and continues south at  the 925mb level (around 2000 ft above ground) through South Florida, finally becoming fully absorbed at all levels near Dade County. Rain showers continue mainly down the east coast on and behind the boundary with a continued chance all day Friday, mainly Southern Portions of Palm Beach County , Broward, and Northern Dade.  High pressure will quickly work east behind the front tomorrow through Friday from western Kansas through Arkansas and finally the Carolinas on Saturday. Pressure gradient wind behind the front as this high pressure rapidly builds east increases over the Atlantic and works in along the Florida east coast overnight Thursday night/early Friday and works down the coast Friday afternoon into Saturday. NE-ENE winds initially in the 20-30mph range will decrease most locations by mid-day Friday but remain in the 15-28mph (esp. South Florida) all day Friday, gradually weakening on Saturday.


TEMPERATURES BEHIND THE FRONT : Not a big cold down, with the most notable temperature impacts interior North Central toward Ocala and North, with other areas feeling lower 60Fs interior to near 65F Coastal East Central from the Port and South for morning coffee. South Florida will not feel much of a change at all. The bigger impact is to the afternoon high temperatures which have been running well above climatology   the past few days, which will return to near or just below normal, but remain comfortable  enough to preclude breaking out winter wear, or for the most part, even fall wear.


BEYOND: GFS continues to imply that as the flow becomes more easterly to ESE just above the deck that some remnant energy from the front will circulate back north toward East Central late Saturday or early Sunday with rain showers resulting, mainly low topped sprinkles with accumulations possible. It is also consistent, however, with ending any rain chance by day break Monday...from which point on, the weather appears will be quite bland with no impacts other than a return to inland fog or low clouds by Tuesday and Wednesday mornings  as winds weaken.


THANKSGIVING: Outlooks for Thanksgiving a Bleak Friday will be included commencing Thursday.   

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