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

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

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

Saturday, March 31, 2012

Outside Activities Should Be on Alert for Stronger Storm Potential Today

Late morning visible satellite imagery distinctly portrays a 500mb vorticity max near the Panhandle (V) moving toward the E-ESE. Forecast models show two players 1)Potential side-shore to onshore east coast sea-breeze East Coast in predominant west to east steering flow aloft and ahead of the "V" and (2) Highest instability toward the south half of the state later today due to the north half (where stronger  mid-level winds preside) high level cloudiness. Thus, the Golden Magic Dividing Rule Lline across Central applies to "some degree" given this time of year of early spring. Best wind fields north, best instability south. WITH, the additive bonus of the 500mb V-max rotating across. Guidance indicates this might break up a bit this afternoon toward the south, running over an east coast/west coast sea breeze convergence toward I95..however...(read on)... 
TODAY: Not too much change in yesterday's thinking as an upper level vorticity max at 20,000 feet (500mb) is noted in the image above by the red "V". In animations, this appears as nearly a closed low pressure system which one would be otherwise be prone to assume was the case without model guidance and surface wind observations. 

This area is forecast to move E-ESE today and across the north half of the state, while lower level winds and frictional effects could generate low level vortictiy and coastal helicity along and east of US1 up the east coast of the state from east coast sea breezes (this is a prime assumption however which can make or break storm strength anticipations!).

Several thunderstorms have already moved across well toward I-10 today, with greater coverage expected to blossom from 1pm on AHEAD of the vort max as lift increases with daytime heating added upon with daytime heating ahead of that feature. A 300 mb jet streak is expected to strengthen toward the base of the 500mb feature across South Central Florida today, squarely placing a portion of Central Florida toward the right entrance region which would increase lifting mechanisms in the mid-levels of the atmosphere adding to upward extent of storm tops, however divergence aloft does not like significant with that feature. This factor, combined with a possible additive factor of low level convergence of the westerly wind / west coast sea breeze confronting the east coast sea breeze front could add additional low level lift from DAB (Daytona) toward Ft. Pierce inland toward I95. 

The factor that would preclude greater lift is that storms should be moving rather quickly today, leading little time for wind field dynamics to assimilate.

There is one other factor to consider however that none of the models have depicted. Should storms to the north escalate 'as expected' and begin to collapse due to anvil storm tops approaching the Tampa Area, that activity could get squelched out from  shaded sunlight, and their collapse could manifest as a large OFB (outflow boundary) propagating toward the ESE -SE which would race ahead into better heated areas to the south under the jet streak winds aloft. 

Anvil tops should stream off toward the ENE today..leaving those areas south of I-4 in better sunlight once activity starts to develop. Outflows have a funny way of moving under areas shaded from above.  With strongest jet stream winds south of SR 528 aloft moving from west to east..if any activity racing and forming in outflow could get either sheared apart or actually enhance, especially along a triangle running from DAB - Altamonte Springs - Kissimmee through the north 1/2 of Osceola County and off the east coast between Vero and Ft Pierce with an even small area as shown below harvesting a higher potential. 

Due note, this image is in considering that an OFB would form, otherwise, much of the activity along the Central Portion of the state might not be as strong, especially if an east coast sea breeze does not form:

RUC Analysis (Rapid Update Cycle) from 11AM shows the vorticity max at 500mb This is over-layed with radar actual, note that some activity has formed AHEAD of the max in the eastern Gulf.  
CONCLUSIVE WORST CASE: Possible strong and ' near severe storms' near Tampa and North as well as near Vero and North especially, with a possible outflow line of storms dropping ESE-SE from North Central Florida later this afternoon after 2:30pm. All guidance indicates activity will conclude by sunset, but timing could be still a bit of an issue considering an aspect of where heating occurs and whether or not an outflow forms, which again, is contingent upon stronger storms forming toward Cedar Key to Gainesville to Ocala areas by early afternoon. If so, strong storms possible in those area with the treat being strong wind gusts in excess of 50mph, and would not be surprised to see stronger gusts toward the East side in the orange and even black areas above if said outflow materializes.

SUNDAY: It appears the front will clear Central almost about the same time the front last Sunday had cleared the area. It will have no effect in regard to temperatures, only to dry out the atmosphere 'A little". In fact, only a warming trend is indicated, with potential 90F + readings popping up for the first time since last September.  

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Friday, March 30, 2012

Warm and Pleasant, Storms Near I-10 Possible

Latest Visible Satellite Image Above: Strong Storms Possible in the Lavender Zone with isolate
thunder eastward to JAX near I-10 later today. Sea Breeze convergence showers and maybe a thunder interior north from near Ocala national Forecast and north. More widespread clouds, mainly north half Saturday with some showers and maybe some thunder toward east Central late afternoon.
TODAY: Another very pleasant day with SE-S winds at 10-15mph in store with some inland cumulus clouds and a few wisps of high level cirrus clouds, possibly more so very late day toward sunset. Latest satellite image shows storms as has been the case for two days near the Loop Current. Highs in the mid and a few  upper 80Fs interior and low 80Fs right along the East Coast where sea breezes prevail. There is a chance of an early evening sea breeze collision toward the north interior, but instability appears to meager at this time, and as forecast, to support much in regard to thunder.

SATURDAY: Winds become more SW-WSW on Saturday and quite warm particularly North Central to South Florida in the potential absence of an east coast sea breeze. Suspect high clouds might run along from I-4 and north producing more clouds than anything else with pockets of showers and perhaps some thunder more likely toward East Central as a frontal boundary of little regard (mostly mid-level disturbance) tries to swing by to the north. The best chance of thunder, if there is to be any, appears will be toward the east coast mid-late afternoon, although if high clouds are absent to the north thunder is possible as well toward I-4 if not yet further north. Rain chances to end by after sunset if not a bit sooner.

SUNDAY: Another boundary will swing toward North Florida with again a chance of showers, but thunder appears to be out of the picture.  Showers most likely toward the east side with westerly winds continuing and highs again in the 80Fs.

BEYOND: Frontal boundary could squeak toward Central but then slide eastward and out of the picture as the part low pressure area will be long gone to the north of Florida with a sub tropical jet stream reminiscent of last October late in the month steering in toward and across Florida. Not much change in temperatures with westerly type winds continuing across a drier air mass.

Another boundary may start to move toward Florida in the Wednesday time frame, but timing is quite sketchy in this regard.   

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Wednesday, March 28, 2012

East- Central/North Isolated Shower Sprinkle Possible

At 1:30PM EDT a cloud line apparently along the outer periphery of a mid-level high pressure system is pressing toward the east central and Northeast Coast. Wind 'could' increase slightly along the coast as it presses on shore accompanied by a  small, isolated shower or two.  The moisture will continue well inland toward the west coast late afternoon and into the evening.
Sea breeze convergence could enhance this otherwise benign feature late today to generate an isolated thunderstorm near the Tampa area today and tomorrow.
Otherwise, a short wave trough could generate severe weather toward the east half of Kansas today. This trough could be the beginning of a pattern change for Florida by the weekend for several days there on out. 

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Sunday, March 25, 2012

Front Dropping South - Slowly (Thunder South Central/South)

ABOVE: Position of front at 8AM this morning, Sunday. This boundary will glide slowly southward through  noon time yet remain across Central Florida through noon time. During this time frame the front appears will begin to 'frag-mate'  with one portion remaining across Central with the other portion sliding southward, especially after 1pm.

The driest of air will be working southward from North Florida but never reach the current frontal position until nearly sunset along the east coast, but sooner toward the interior and west side of the state (lower dewpoint temperatures)...

Further south along and ahead of the primary boundary there is a slight chance of  isolated thunderstorms  , but mainly showers.  Cloud cover could linger toward central (party cloudy) until after sunset to varying degrees due to continued mid-level moisture overhead this area. 

Wind today behind the front will be from the WNW-W and gradually weaken and shift more toward the NW after dark becoming very light toward early Monday sunrise time. Stellar weather on Monday.

Winds then become a bit breezy Tuesday from the east  with a period of cloudiness and the possibility of showers (although timing of this 'possibility if even that' remains only somewhat sketchy as a second boundary  of 'moisture convergence'  swings through the south half of the state accompanied by the stronger winds for this day only.

 After Tuesday, the remainder of the week  appears will remain uneventful and quite pleasant with highs in the lower 80Fs and upper 70Fs near the east coast. Coolest east coast morning will be Monday with the NW winds, but once those swing to onshore heading into Tuesday it is back to status quo temperatures other than where clouds could be more prevalent on Tuesday.

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Saturday, March 24, 2012

Strong to Near Severe Storms Possible Esp. East Coast

Annotation for the 4pm time frame based on the Rapid Update Cycle (RUC) Weather Forecast Model. This image shows 'precipitable water' (PWAT) air, sum total moisture amount in certain levels of the atmosphere, in brief. The purple shows where it is 'possible' some stronger storms could occur; although, further north central could experience storms a bit further inland from the coasts as well. The 'blue' "Severe?" is a questionable area of interest from Southern Volusia to coastal Central Brevard for sole reason that the North American Model and RUC are showing rather strong upward vertical velocities along I-95 East Central Brevard specifically, as has been the case for 48 hours for the most part in previous runs.
For continuity, this shows the location of the upper level 500mb low today. Recall this low originated toward northern New Mexico several days ago. We can see also the next trough approaching the Western U.S., with a 'ridge' in between the two, much and not unlike two waves on the ocean. Those along the ridge are 'riding high' with nicer weather today in regard to rainfall. This is a forecast valid for 4pm EDT.

TODAY: A frontal boundary mostly defined as far as Florida is concerned by drier air behind it is  well to the north of Central and barely in the Panhandle yet still. This boundary will be across Dead Central around noon time Sunday as it stands now, give or take an hour or two.

Westerly winds today across much of Central and North Florida through noon time. Expecting , as yesterday's post mentioned, that perhaps a side shore up-river wind could develop from South Central toward  Volusia by mid afternoon. Steering for rain to move from today should be generally from the west around 12mph South Central and Central and faster further north toward Ormond and JAX due to closer proximity of the 500mb low shown above.  Vertical Velocity values from the 925mb (2000 ft) up through 700mb (10,000 ft) are coming in very respectable on the latest morning RUC model, as was  mathematically theorized by the NAM for the past two days near Central and parts of Southern North Central, especially near the coast. 

With a side shore wind (if indeed this manifests which is the BIG player today in regard to potential severe weather)  *possibly a bit 'gusty' and only apparent EAST of US1*, storms crossing the rivers from Volusia toward possibly Southern Brevard could acquire some local enhancement as they approach the coast. Temperatures well aloft are more than cold enough to provoke greater upward buoyancy, although surface based convective instability is not overly impressive, although ample.

Else where, some stronger storms due to greater winds aloft are possible toward Ocala, Orlando and north to JAX/GNV as well as south toward Northern Osceola County, into areas around Sanford for example toward Mims/Titusville, Oak hill, Scottsmore, and south perhaps as far south as Cocoa Beach to Satellite Beach. The jury is out regarding further south toward West Palm Beach or toward Martin County, but have not included this area in the graphic due to lack of greater moisture availability for strong storm generation south of Brevard County in this post.

Forecast soundings continue to show temperatures aloft as noted yesterday, and NAM forecasts from overnight indicated a shallow inverted 'V" type which would indicate a potential for Cold air to drop through a shallow dry layer enhancing surface wind gusts. Small hail is possible as well, but 'severe category' hail is unlikely due to lack of greater instability, but it could come close, hence the 'severe' annotation for 1" hail in one storm or two..and stronger wind gusts toward 58 mph... It appears the highest rainfall totals are possible over North Central along and near I-4 and north as well as a bit south. Rainfall totals though are not necessarily equivalent to storm strength, as those areas could be receiving rain prior to the time that the atmosphere could become most unstable. Thus, the greater VVs are further south.

SUNDAY: The "dry front" will be close to Dead Central sometime around 11AM-noon, with a chance of showers any time after midnight along and ahead of it across North Central and Central. The front will then proceed southward during the day with dry air following on NW winds. Clearing from North to South late morning through mid-afternoon.

Chance of Storms on Sunday will be greatest along the East Half of the State from Palm Beach County to Miami, and some of those could be strong as well, especially into Broward, southern Palm Beach County, and Dade..possibly toward Key Largo.

BEYOND: The upper (and mid-level low not shown) will be pulling off to the east, and so far guidance appears to indicate another 850mb trough will swing overhead with greater moisture stacked up along that as well., possibly another very shallow boundary underneath. Winds becoming NE-ENE-E overnight Monday into Tuesday at 12-20mph during the day and perhaps cloudy with a chance of showers some time on Tuesday, ending by the time we wake up Wednesday morning. No rain is foreseen beyond toward next weekend at least...although this time frame needs to remain open-minded for greater scrutiny in the next few model runs.

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Friday, March 23, 2012

Late Showers/Iso-Storms Interior North - More Over Weekend

Forecast track of upper 500mb trough/low for later today and located near SW Illinois. This image shows the annotated previous location per red arrows from Arizona in the previous post and how, in general, it has proceeded ENE ward the past few days.
This image shows the approximate location for Sunday afternoon..note
the displacement from Illinois SSE-SE ward toward northern GA. Florida
is at this time now in strong winds (blue) aloft

FRIDAY: Happy Spring Renewal Time !  Did you get the cobwebs cleared from winter mentality?  I hope there is a spring in your step and mind. The skies and temperatures over Florida have been fabtabulous with few clouds, and quite!  Much more in that regard for South and South Central today, but interior (later today) and North Florida is a different story.

If you received a blog post yesterday and actually read it, it is time to inform that was not of my doing. The 'poster blog system' erroneously sent out an old post. Apologies if this lead to any confusion. 

Today the upper low will have little effect on the state except toward the Western Panhandle toward Tallahassee as we will see further down in this post. Further east and south into the peninsula it appears ample moisture will be available for a late day east/west coast sea breeze collision time over and near the spinal interior, especially toward JAX-Gainesville region, and possibly working south along the east/west coast seabreeze collision late toward Western if not Central Volusia County.

Further showers could be set off well toward the SSW into Polk County at least, as I see the Storm Prediction Center is playing one model that far south. Although, I am siding more with the GFS and RUC and current without any activity South of the Tampa latitude looks 'questionable' as of this hour..but the region of all encompassing possibilities is included in this graphic.

 and this one
NOTE: this is the latest radar image, see the severe thunderstorm warning along the Florida/Georgia Border as indicated by the yellow box. This area is shifting Eastward slowly along with the upper low. The orange is where thunder could occur today..very spotty if at all south of I-4, but would not sell Lake County Short if not Polk (not shown in orange). I left a 'gap' across Northern (central). This line of reasoning is because believe activity shown on the peninsula will be due to sea breeze collision activity and outflows from that.
Saturday**: Frontal boundary to continue eastward, although poorly defined at the surface yet still; however, the activity that is being generated to our NW in the Panhandle today will re-emerge on Saturday toward Central Florida. Per trends of past three days, and fairly good model agreement, believe some activity (very very isolated) could be "strong" with small  (marble)  hail all East Central. This looks like a case on Saturday for a stronger side-shore type 'sea breeze' to form toward mid-late afternoon remaining pegged along US1 toward I95 at most, with steering aloft toward the E or ENE at 12 mph or so. Instability will be ample but not truly 'amped up' to warrant a higher threat . Temperatures aloft around -12C at 20,0000 ft and near 5C at 10,000 ft. (compared to -5C and 10C respectively  in summer, we can see those temperatures aloft tomorrow are much colder than in the summer when we have some strong storms by at least 5 degrees). But, it will still be warm at ground level. Models agree on Vertical Velocities (upward motion) very consistently model run to model run near and east of Orlando exiting off Central Brevard toward 6pm or so. With this line of reasoning, thunder storms seems a good bet somewhere across East central toward Tampa mid-late afternoon through early evening...and one or two could be on the strong side. Does not seem SPC will issue a "See Text" soley due to the isolated nature of this 'potential' activity, and if at all, mostly along the I-95 toward US1 to off the coast zones.

Sunday: The frontal boundary to be pushing through Central mid morning toward noon. Showers and thunder could again form during this time, especially after 11AM toward South Central. BUT, details get sketchy this far out in time though, especially since the  previous GFS is much faster than the NAM.  As of this morning, the GFS is slowing down though, and this seems feasible. With that , thunder again possible from the Central Dividing Line (affectionately labelled in these posts as the "Magic Dividing Line" running along SR528 ...) into South Central...and perhaps even SE Florida toward Palm Beach County./Dade mid-late afternoon and early evening...before the front clears the state.  

The Front: This front will be more or  less acting like a non-dynamic 'dry line'..but not anywhere near that seen in the Central Plains. Although Monday morning could be a bit cooler than past mornings and damp, sunrise will yield to much drier air as low level moisture mixes out into the dry air just above ground resulting in a warm and dry air (literally and figuratively) day Monday afternoon with a NW wind. Good day to hang the clothes out to dry if doing laundry. No rain expected again for a few days beyond at this point.  

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Tuesday, March 20, 2012

Cont'd Breezes - Wednesday Showers A Good Bet

IMAGE Depiction,  per the latest Rapid Update Cycle (RUC) Forecast Model,  the jet Stream position later today at 30,000 ft (feet). Note the unusual southern extent. Coldest air at ground level this time of year is typically near and north of the jet stream, which explains then the snow in parts of Arizona. This also shows how warm air has managed to reach across all of the Eastern States into the eastern Plains and as far and further than the Canadian Border as has been the case for several days. This trend was well depicted by models several days in advance.

TODAY: During the course of today the trough shown above will move slowly east north east in general into the weekend and be a rain and potential severe weather maker from time to time along its course.  An associated cold front will be a very slow mover as a consequence, considering today is only Tuesday. 

Weather appears  fairly juiced up for eastern Texas into Louisiana later today and northward to a  limited extent for severe thunderstorms and possible tornadoes, but a outbreak of any sort is not anticipated. Meanwhile, high pressure circulation continues the Florida east coast onshore flow. The pressure gradient will be holding its own tonight through tomorrow as winds become a bit more SE toward tonight. Additionally, forecast model trends are sticking closely together, depicting a well defined 'bubble pocket' of high precipitable water (PWAT) air to move in after sunset to after midnight toward the southeast coast which is then to work north and west through the course of Wednesday.

WEDNESDAY: As noted above, higher moisture content air to spread in over night.  This moisture appears to be getting drawn toward that humongous trough to the west as it steadfastly shifts east  ever-so-slowly toward the Mississippi River. Below is a hand-made graphic showing where this moisture and potential showers will work in. I did not include thunder for the early morning activity, although I could be selling the weather short. Latest NAM forecast weather balloon soundings do not appear to exemplify an atmospheric structure which would be support a cause to argue for thunder producing showers early on, or not at least until later in the day. By that time, the leading edge of the bubble of elongated moisture will be well inland during the course of daytime heating. The SPC (Storm Prediction Center) is not indicating thunder tomorrow other than toward Gainesville, but I am not prepared to deny areas further south some thunder as well as shown in orange below:

Above graphic for Wednesday. Green along east coast shows better moisture for producing clouds and showers spreading WNW per the black arrows during the day, reaching NW Interior toward western lake County, Ocala (perhaps) toward Gainesville after 2pm. Meanwhile, the east coast areas should be ending with the rain chances by mid-late afternoon, although clouds will remain present to a certain degree. The moisture for these showers, coming off the Atlantic appears it could work toward Alabama or Georgia in the next two days.

SATURDAY/SUNDAY: The deep elongated trough will be 'cutting -off' in the next 48 hours. Meaning, a closed low will form. Although model guidance is in fairly good agreement right now, closed lows are messy business to contend with in regard to how fast they will press onward, and in what direction. However, given the present circumstances combined with those yet forecast toward next week (more below), it seems relatively safe to assume they have nipped this closed bugger in the nip. 

Given that notion, best now to stick with model agreement but no-thing is dead pan certain concerning the weekend weather in regard to rain chances for Florida as a consequence. 

Lest we be left slap jawed and dumb happy, latest guidance indeed shows for a chance of thundershowers and/or showers, especially on Sunday as by now the cut off low is moving off the east coast or near to close to it. A weak frontal boundary will be entering the area of Central mid Afternoon Sunday. Winds by Saturday will have already started to become much more southerly on Saturday if not SW-WSW on Sunday. There is a chance there will be an east coast sea breeze pegged east of the spine of the state if not closer to the coast Sunday afternoon as the front sinks down the state. Best chances of thunder appears to be North Central to Central east side and south to Dade County beyond 2pm Sunday...

BEYOND: History repeats itself in more ways than one. Another deep trough to move into the West coast akin to a pattern we might see in a La Nina January, or reflective of it.  That combined with a negative Atlantic Oscillation (AO) would be the culprit I am 'thinking' for the "double dose of deep upper level troughs parade" toward the U.S. east coast. It is this approaching trough that will boot the prior cut off low as just noted out of the picture toward the early portions of next week, yet to make room for the next one to the western U.S. 

And now, the rest of the story...This next one could be even more extreme than the previous, so be ready to hear more weather ready recaps on the national news networks, The Weather Channel, onward and upward...up through next week... 

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Friday, March 9, 2012

Strong Storms "Possible" Today - Wretchedly Windy Coastal Weekend

Note Captions. Factors pro/con for any storms today in the body of this post. Any storms that can manifest today , especially after 3PM have the potential for hail and/or strong wind
TODAY: The boundary/front noted yesterday continues Southward as forecast now across the Deep South, although the timing of its approach and passage on Saturday is a bit sketchy now per the morning North American Model (NAM). This post is based mainly on the current trends locally though, the RUC, and the GFS model, and an earlier run of the HRRR model (which I have not viewed again during the past 2 hours, so things could have changed). It is worth noting that should the NAM verify, conditions will not be quite as 'wet' which is feasible given the current situation atmospherically across East Central Florida, with better conditions for a storm or two <not shown here> toward Martin County , St. Lucie, or even Northern Palm Beach Counties. Otherwise:

Cloudy conditions over East Central this morning should break up a bit by noon time. Light sea breeze Central and North Eastern Coasts likely after 12-1pm, but should not make much   inland penetration beyond I-95 or 'so'. Temperatures aloft are quite cold today, with 500mb running around -12C per the KSC morning sounding (in the summer with our storms they were a much warmer, 8-10 +C ; this makes for a good 15-20C difference in how cold aloft the air temperature is today as opposed to during the summer. Cold air aloft makes for strong storms. 

The atmosphere is much drier today than in summer, but drier air can equate to more isolated activity allowing for storms (if they manifest) to not compete for the Convective Available Potential Energy (CAPE) that will be available, which is less than in the summer. It also allows for decent of cold air thru the drier layers, making for strong wind gusts at ground level. 

In short, we have competing factors pro/con for storms today. A 20,000 ft (500mb) wind increase is expected to surge across the north half of the state toward early-mid afternoon which should add additional lift to the mid-levels of the atmosphere. A con for storms would be the poor lapse rates showing up on the NASA/MLB LDIS graphic,  but those seem to be becoming more supportive during the past three hours as time goes by.

Steering today from Central to North Central will be from the west to east around 10 mph; however, the very cool sea-breeze will likely prevent any storms from penetrating much further east beyond the east coast sea breeze boundary, sapping them of strength due as they 'ingest' this cool air at ground and low levels of the atmosphere which causes activity to 'erode' along the forward moving flanks of the storms as they enter this relatively 'cold' sea breeze.

As such, storms (if they do occur) 'could' appear to move very little due the persistent 'progressive erosion from the east coast sea breeze. With this in mind, it is possible that some areas if storms manifest could see up to 1.00" of rain west of I95 toward Orlando, Osceola , Seminole Counties for starters, but any such manifestation will be very isolated. With the cold air aloft in place any stronger updraft in a generated storm (again - the pre-requisite for any storms in the first place is an updraft of significant strength which is a bit in question) could produce hail and frequent lightning . 

The NWS (National Weather Service) alludes to a potential of small hail. Whether or not it reaches severe size (1.00" in diameter) is definitely debatable considering the other factors that are either lacking or those that are too weak to support severe sized hail today. I suspect storm motion will be rather slow either way, but considerable cloudiness at least will over spread much of the entire Eastern Central State by later today due to shower or storm cloud debris moving from east to west above the depth of the sea breeze boundary. 

As noted in the above image caption, activity could be very isolated due to persistent East Central Cloudiness early today. If those do not break up, all bets are off for strong storms, with possible storms (or one) further south toward the NE-E shores of Lake Okeechobee.

Any rains, wherever they may (or may not be), should cease shortly after sunset with lose of daytime heating.

SATURDAY:  As noted a few posts ago, it looked like a repeat of the previous windy front (although at that time this was a questionable presumption, admittedly).  Meanwhile, the cold front will mainly be sliding off shore the U.S. East Coast to the North of Florida with the tail end skimming past Central anywhere between 7AM Saturday morning to mid-afternoon. For this post, I'm siding with the GFS consistency over the NAM's; this too, bears watching though. Either way, this 'backdoor' type front will be accompanied after passage by increasing NE-ENE winds of 20-23mph with gusts possible of 36mph near the east coast, as well as some showers from near Volusia County to coastal Brevard from the time of its immediate passage and up to 12 hours afterward. Very breezy, especially near the beaches overnight Saturday night.

SUNDAY: The wind surge due to high pressure building rapidly eastward beyond the front will force the moisture convergence band (remnant front) southward and down the east coast overnight Saturday and into Sunday as rain chances go to zero for Central. Wind will continue breezy, although not quite as strong as what potentially lies ahead for late Saturday and  Saturday night.

Rip currents will be a 'big deal' this weekend, considering the insurgence of  inexperienced guests from the northern climes who may not be as fretful of entering iceberg temperature water.

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Thursday, March 8, 2012

Variable Clouds, Eastern Showers Possible, More Likely Friday

Afternoon synopsis per the Rapid Update Cycle (RUC) Weather Forecast Model. Note the boundary now across the southern toward the NE portions of the U.S. Much rainfall is occurring along this boundary as has been implied for several days now. That boundary will be pressing east and slowly sink south into Central Portions of Florida early Saturday, barely!
TODAY: At least the wind has let up today, and as such coastal afternoon high temperatures will be warmer with less impact of wind blowing over cool water and sloshing the cool ocean air into those communities. Otherwise, little change in the local region. As can be noted above, a high pressure 'ridge axis' from a high centered yet further off the image will move very little although should sink slowly south with time as the front moves east. All in all, it appears that frontal boundary will barely clip the eastern shores of Central Florida before complete frontalysis occurs, leaving only a remnant moisture convergence band which could work down toward South Florida before even that depletes itself (Sunday time frame going into Monday). Meanwhile, comfortable temperatures in the mid-upper 70Fs and warmer west half of state and possible showers and overnight lows in the upper 60Fs to near 70F along the east coast, especially Brevard and South.

In the image I've colorized areas that could see a shower today ..the lavender in general is where the greater concentration of rain has been occurring along an old moisture convergence band from the previous frontal boundary. This band has lifted north a bit from Broward County (yesterday and earlier today into Palm Beach County ). Do note the  'enhanced 'area off Indian River County in this image. Radar shows showers moving toward Central and North Central Brevard, but at this time they are 'eroding' as they close in on the coast; possibly  due to cooler near-shore waters. Whether those showers will make it to shore is yet to be seen for the most part, and this has been the case for a few hours today so far. However, the blue area along Brevard mainly indicates that 'something' could very well reach the coast by mid-afternoon through at least mid-evening.  

FRIDAY: There are still indications that if it is going to rain solidly almost anywhere in the next few days (other than the area in South Florida like today) it will be on Friday from just north of I-4 and south. The GFS is very generous on this possibility from early morning (at the coast) to the entire state along those bounds as heating of the day commences. Suspect there could be some thunder given the cold air aloft, but there is little in triggering mechanisms other than perhaps some mid-level disturbance (minor) per the GFS. The NAM continues with advocating a possible sea-breeze collision toward Orlando (west side) late day in which case I believe would be thunder; other than that, it speaks little to rain chances elsewhere.Comfortable 73-77F degree readings. 80Fs west side of state away from any potential east coast sea breeze.

SATURDAY: The frontal boundary shown above will slide mostly eastward but sink south with time. In doing so, it will  absorb within the high pressure area depicted and wash out (frontalysis). Moisture will remain present ahead of this boundary, along it, and just behind it through Sunday as it side swipes Central Florida toward Palm Beach with time; thus, clouds and possible showers seemingly like today are possible through Saturday working from northeast Florida toward Central, and eventually Sunday (South) with a lower likelihood. 

As such, acting like a backdoor cold front as it were, a wind surge is possible behind the boundary remnants working down the coast as well with winds for a time similar to that of Wednesday. The fun-n-games with this boundary all regions should be over with by Monday through Wednesday at least with no change in the temperature regime of something like that of today..with little to no rain chance.

BEYOND: The next front so far is showing to behave in similar fashion if even that, with the overnight GFS showing no FroPa (frontal passage) going into the 3rd week of March. Realizing, any forecast beyond day 6 under the current circumstances is suspect...beyond the normal "template of suspicion" which is usually about 3 days. Sound the all clear.

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Wednesday, March 7, 2012

Winds To Taper Off Thursday As Chance of Coastal Showers Increases

Latest Satellite Image as of 11AM EST. Note: 1) To the right is the white line delineating a break in cloud types associated with high pressure in the middle levels. Those clouds appear to be missing most of the state north of the line, although an offshoot of them continues to impact the coast which will likely work across the state during the noon hours. 2) The Blue arrows show the motion of some high level cirrus clouds impacting mostly the North 1/3 to 1/2 of the state from time to time. These clouds could increase in days ahead, especially later on Thursday into Friday. 3) The green area is where showers are and could occur today, working north with time (yellow) to as far north as Southern Volusia (light blue) by Thursday noon time. Otherwise, partly cloudy to mostly cloudy skies should persist.

TODAY: Very breezy at the east coast beaches spreading inland during the day. Winds will remain overnight at the beach but be notably less 'breezy' heading toward mid-evening, while they decrease significantly inland and away from the beach. Overnight lows similar to last night with mid-upper 60Fs along the coast and mid-upper 50Fs inland. Showers around the Keys would work north into Dade County later today.

THURSDAY: High pressure NE-ENE of the state in the mid-levels and surface reigns supreme; however, near the 850mb (5000ft) height the ridge will weaken and pull off more to the east of the SE states into the Atlantic and in doing so the wind at this level will become more Southeasterly to SSE and draw the shower generating moisture well to the south of Central northward. 

Expect that moisture convergence along the east coast accompanying this mid-level moisture up through 10,000 feet will potentially have enough atmospheric depth (just as if one were to go deeper into the ocean of water, we can go deeper 'upward' into the depths of atmospheric moisture except it is coming to the east coast instead) .  In turn, showers could form mainly east of and along I-95 and work north toward Southern Volusia perhaps by early afternoon on Thursday. It appears the area further to the west in the state will remain too dry for showers but either way the clouds persist as winds all regions die down even further.  Outside of showers continued warming with highs in the upper70Fs toward lower 80Fs on the west side of the state in particular.

FRIDAY: Higher clouds (the blue arrows) will continue as they ride over a bit of a 'dirty ridge' (the clouds) located well aloft in the atmosphere to the west of Florida. Those cloud will be generated by moisture from a trough located near the Desert SW Region moving into Texas, ejecting high level moisture up and over the ridge and across Florida...thus spillage of high clouds, or 'dirty ridge syndrome'.  Outside of those clouds, the low level ridge will be close to Central Florida with very light winds. Sea Breeze convergence and if enough heating can work in during the day, destabilization enough for a possible thundershower in the Western Orlando area toward Eastern lake County or Northern Osceola County. Sea breeze although light but very cool in comparison to inland highs in the mid 80Fs  on Friday will keep any showers or storm from reaching the east coast with the light steering currents in place by that time as well.

BEYOND: Continued moisture in place over Florida as the frontal boundary which will likely be quite problematic for parts of North and Eastern Texas, Arkansas, Mississippi, Tennessee (in general) becomes stretched from East to west and sinks slowly south toward Central Florida. Showers could be in our area with this boundary as well during at least the first parts of the weekend if not the entire weekend for the north 1/2 of the state (and possibly southward as well) although for now the more likely scenario spells out at least more opportunities for clouds. No cold air yet is on the way!!   

This  boundary might come in to being a big player for a repeat of what we are experiencing today but with rain showers as well. The next boundary behind the forthcoming boundary of this weekend (which will create showers) might not even reach Florida at all.

 Recall: The previous front which made it fairly cool for 36 hours made it to the Florida Straits and washed out (the showers down there today), then the next boundary should make it toward Central (this weekend), then the next one sometime next week not even that far south. Thus, each front is progressively making less southward penetration across the state, and in turn, no cold air.

In closing today's observational and preliminary (and quite unofficial analysis) forecast, I've noted that sea surface temperatures are generally running nearly 5F degrees warmer than they were last year around this time for the area off Cocoa Beach and North.. ..which can be attributed to the fact that this has been a mild winter all along the Eastern United States from North to South.  This could play in to future forecasts as we head toward the last week of March and into April in regard to a number of things yet to be determined.

"Cat Does Not Try To Wise. It is All She Knows"

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Monday, March 5, 2012

Quite Pleasant (!) Today - Backdoor Front Tonight

Global Forecast System Model (GFS) Valid Valid For 1AM tonight (Tuesday early). As noted a few posts ago, another boundary would skirt by to the north; and high pressure, as we see above, will rapidly press eastward behind it. The result being a surge of NE-ENE winds overnight tonight toward early Tuesday, especially toward daybreak with increasing low level type stratocumulus clouds as well during the day

TODAY: "Chamber of Commerce" Day in store with highs in the low - mid 70Fs. Clear sky and light wind from the WNW-NW ahead of another frontal boundary. This  frontal boundary referred to a few posts ago will skirt by to the north mostly, but the tail end will cross East Central Coastal area 2AM overnight tonight in 'backdoor fashion' (from the NNE direction as opposed to from a westerly direction as fronts normally more from west to east). The winds in the mid-levels by that time will already be from the NE despite surface winds from the north (light) before then. As the front passes we could have a 'surge' of stronger NE-ENE winds and increasing low level moisture from the Atlantic, most notable all day after day break Tuesday.

TUESDAY: Believe it will be 3-6 degrees cooler mainly Central and North on Tuesday with highs in the upper 60Fs to lower 70Fs toward the east side behind the boundary's passage with stratocumulus clouds all along the entire east coast. Warmer south. By late afternoon a few sprinkles are possible mainly north of Vero Beach close to the beaches. Guidance is 'up in the air' over exactly how much if any rain will fall. Believe the NAM rainfall showing measurable amounts central by sunset might be over-doing it, but will monitor this and continue to compare with the GFS which shows nothing but sprinkles (at most) except increasing chances toward far South Florida heading into Wednesday.

WEDNESDAY-NEXT WEEKEND: No change in the pattern. Winds could be a bit gusty, especially at the east coast beaches Tuesday-Friday with periods of stratocumulus clouds gradually abating with time to a lesser degree, probably spreading inland during the late morning hours, with some sprinkles at the coast (possible). Low and high temperatures will vary very (very) little along the immediate coast between night and day (by perhaps 7F degrees) and remain in the mid to upper 60Fs overnight and lower-mid 70Fs day time. In other words, east coast temperatures will be dictated by those of the near shore waters.  Again, will need to monitor for showers, but as noted yesterday it appears the depth of atmospheric moisture will remain too shallow to foster much more than a sprinkles other than toward late Wednesday far South Florida and Keys.

BEYOND: So far, no cold fronts are shown to impact Florida for quite some time as a short-lived 'blocking pattern' aloft sets up well west of Florida in the South Central Plains toward the Mississippi. 

This pattern, although preventing fronts from reaching Florida while high pressure and onshore winds continue over the state, will generate persistent stormy and/or rainy (heavy) conditions toward East  Texas, Louisiana, Arkansas, and Western Tennessee specifically. If any severe occurs it looks like it will Louisiana and Southern Arkansas, and perhaps West Mississippi. 

Expect we will hearing in weather headlines in days to come a new story going from tornadoes (as was the case) to floods from late Tuesday through at least Friday in that area.  

For Florida, to verdict is in for  little change over much of the state (especially toward the north half into week 2 of March);  could have more clouds and rain chances as well once that blocking pattern starts to break down and shift the remaining moisture eastward toward middle of next week. When the pattern will break is up for grabs though despite (in my opinion) what the models are showing. No temperature issues at all for Florida are shown for the next two weeks (fingers crossed); thus, indeed that cold blast of a week ago as noted previously might have  been the last one of the winter .  Any rainfall this time of year is welcomed as we are now and have been in 'the dry season'.    

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Sunday, March 4, 2012

Clearing Through the Noon Hours - Much Cooler Through Mid Morning Monday

Front on Radar (Time noted)

A Severe Warning went out for near Daytona Early and in this location around 830AM

SEE TEXT For Today. No changes otherwise from previous post

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Saturday, March 3, 2012

BIG Weather Changes Statewide Through Sunday

Current Noon Satellite Image with 'Blog Regions of  Consideration' Through 2pm Sunday.
Details in Text Below. Note captions in Full as Written in the Text. (this image also points at the "Lake Shadow" (of cloud free sky) right now due to SW winds blowing across stable Lake Okeechobee water's air)

TODAY: Cold front has entered the far western Panhandle of Florida and will progress only slowly today toward the east. A weak but stretched out area of low pressure is to form as guidance all shows along the Northern Gulf which will slow down southward progress during that time frame today and into most of the evening. Therefore, SSW-SW winds to continue today, with highs in the mid-upper 80Fs Statewide. It is possible that winds will increase a bit toward dark as far south as Dead Central as 2000 ft level winds (at 925 mb-- millibars) increase and translate to the ground. After which time, winds will remain overnight tonight from the SW to a slightly lesser degree except in the area immediately ahead of the front in North and North Central Florida toward early Sunday morning before Sunrise.

Current Front Position and this post's (not official) projection of its location
through 7AM (orange). The front will clear South Florida between 2-3pm Sunday. Also not the areas where Severe weather is 'possible' , but not everywhere. The chance of severe thunderstorms decreases south of the southern Red Line, although this is questionable,   threat could exist yet as far south as lavender if not more so
.  (Thinking the front could be delayed by as much as 2 hours) 

TONIGHT: Continued SW winds tonight and increasing clouds after dark from north to Central after 3AM. Overnight lows in the 60Fs after midnight. The front is shown by morning models (which are in close agreement) to be close to the Central "Dividing" Line (near SR 528 on the east side) around 7:30-8AM. Rain chances should begin generally one-two  hours prior to frontal location. Surface winds also increase around the same time. One can take this projection and translate it southward with time for those interests in far South Central and South Florida heading into late morning toward noon.

EARLY SUNDAY/SUNRISE: First off, I notice the latest RUC has a mid-level 'wind speed max' now showing up around 2AM west of Central Florida in the east central Gulf. This feature, if it is true, could result in needing to throw in a "Severe Risk" further south than the lavender line above and more toward Okeechobee as well as a slight delay across Central of the front's passage. 

Otherwise, be prepared for a period of rain and strong wind in the vicinity of heavier rain showers as the front approaches and possible severe winds (at or above 58mph as noted in the graphic). Winds just above 'the deck' are forecast to be nearly 50 knots at least, so down drafts if in only rain showers could result in surface winds in the 50-55mph range for a brief time as far south as South Brevard. 

I have included a schematic from the GFS model of the forecast Jet Stream Winds at the time the front crosses Central as a reference. These winds will never cross South Florida to such an extent, and realize also that the strongest mid to lower level atmospheric winds appear will pull out and across Florida north of Lake Okeechobee in the 35-55mph range (thus, the less chance of storms further south), given the steering of these winds at higher atmospheric altitudes.

NOTE strength of winds at jet stream early Sunday in blue squares, and front position at the same time. The fronts position in this graphic assumes a slight delay in passage across Central as opposed to the earlier images.

SUNDAY LATE MORNING THROUGH DARK: Outside of any severe weather threats (mainly only in wind south of Volusia County) and the good chance of some measureable rainfall (mostly north of a line from Vero Beach to Sarasota) a lesser degree further south, prepare for a RAPID FALL in temperature behind the frontal boundary by as much as 15-20F degrees in the first 1-2 hours if not more. Thus, the high temperature on Sunday for folks in Central will occur near sunrise, with a noticeable fall after 8-9AM. Temperatures in the upper 60Fs to low 70Fs for instance could fall into the lower 50Fs by 11AM- noon. After and during this time, we can expect rapidly clearing skies and much drier air to move in on brisk NW winds of 15-32mph .  Only expect a slight rise in temperatures toward 60F, but winds will keep things on the cool side regardless.

LATE SUNDAY: All but perhaps the Keys will have cleared. Very cool temperatures.

MONDAY EARLY: Given the now lighter winds that will occur a few hours after sunset, but continuing from the NW-NNW, it appears one of the coldest spots in the state could be toward South Brevard County of all places and into Indian River County. 

All locations west of the Barrier's of Brevard and south will likely be in the lower to mid 40Fs, but would not be surprised to see upper 30Fs in the area noted above as well as much further north. Sky clear with lower winds, although heating on Monday could mix some winds to the ground to make highs in the low-mid 60Fs feel 'too cool' by comparison, but really not bad out of the shade. But this will be short-lived as winds die down toward late day. Outer Barriers of Brevard and A1A corridor to the south could see a low closer to 50F. 

TUESDAY: Little change in philosophy from past posts. Winds to becoming ENE overnight, with a possible surge in winds with some clouds by late morning if not sooner. No rain but highs in the upper 60Fs to lower-mid 70Fs possible already.

WEDNESDAY and THROUGH THE WEEKEND OF NEXT WEEK: Easterly winds for the duration, possible gusty at the coast after day break each day in the 12-22 mph range. Possibly more cloudy than not near the  east coast with a chance of sprinkles or light rain at any given point in time as Atlantic startocumulus clouds work ashore, although not much (if any) accumulations expected. The atmosphere will be too dry above perhaps 5000-7000 ft above ground, hardly enough depth of moisture to generate anything beyond a sprinkle or quick rainshower.   

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Friday, March 2, 2012

BDoF Tornado Threat Far To Florida's North, Storms 'Possible' Early SundayCo

Cold front position forecast this afternoon with low pressure centered over Indiana. The area in orange is  'my personal annotation' for where very strong, tornadic (tornado producing) type thunderstorms with strong winds and damaging hail could most likely occur today. That area is most definitely not all inclusive as will be seen in the next graphic.
TODAY:  Big Danger on Friday (BDoF) - Dynamically powerful early March storm system and related cold front is driving across the Mississippi/Ohio  River Valley Basins today, while in Florida the weather is not unlike that of a peaceful, early April-time. This will be the case again tomorrow in Florida with even warmer temperatures. Sea Breeze east of I95 if not US1 I expect will manifest within the next hour (it is now 1:45pm, Friday). Highs in the mid 80Fs and lower 80Fs near the coast. No rain. 

Meanwhile, further to the north exceptional wind dynamics mainly are the core reason for generation of thunderstorms that start to rotate (likely as rain-showers and before even becoming thunderstorms) further north. Winds from accommodating directions for cyclonic rotation coupled with 'energy' and cold air aloft could generate strongly wind driven large hailstones and vortexes of wind energy in vertical columns, tornadoes. Some could be long tracking and quite strong. The Storm Prediction Center (SPC) located in Norman, OK and likely ALL news networks in the most to be effected areas are heralding the alert for this potential. One can turn on The Weather Channel to keep up to date. In fact, as I type there are 5 tornado warnings in place over a part of the very large area of concern. See below:

This graphic is for the tornado 'risk' determined by where a plethora of weather conditions combine just right to result in rotating storms. This lavender area is matched up nicely with the core concern for this blog's purposes in the first image. This image is updated at scheduled times by SPC which also issues Watch Boxes. Warnings are issued by respective National Weather Service (NWS) offices in any area that such a storm is manifesting or already in progress, whether that storm is or is not in a previously issued 'watch box' . This graphic does not show the wind and hail risk as well, although for the most part they overlap. The tor risk is a smaller than the much large general severe weather risk area.

FLORIDA SATURDAY: Another day of warmth, possibly near record highs East Central from South Central toward Daytona Beach. No sea breeze and only a few clouds as the cold front moves into the SE states and the panhandle. The front will enter the panhandle slowly Saturday night with a chance of stronger storms in this location as well. I have made a 'personal edit' to the last issuance of the SPC day 2 outlook as can be seen here:

Based on 7AM morning model runs, there is a slight chance
of severe storms overnight Saturday into early Sunday per the official outlook area, The southern orange line  "could" be extended as far south as shown, but do not that is only a personal observation based on model trends. This is due to the strong wind fields the morning model runs are showing that the previous runs (on which the original graphic is based) did not quite show those winds.

SUNDAY: Very close model agreement that the front will cross Central from NNW-SSE between 5am to 10am (north to south)..and cross very close to Orlando around 7:30AM Sunday morning. Strong wind fields just above the deck could result in either thunder or simply rain with winds in the 45mph range at least if the morning model runs verify, especially on the east side of the state.  A very powerful jet stream wind departing just to the north of Florida will place all of the state in the 'left exit region' which add substantial lift to the atmosphere, and the latest models are showing winds at 2000 ft over 0ver 40knts exiting off the east coast from near Indian River County and north through 11AM or so.  Chance of rain dead central to begin close to 6AM and abating by 12pm time frame...with a possible thunder chance extending further south to the keys (not shown in the above image either).

The front will be close to the Keys by  2pm, with clearing over Central commencing around noon time and working south with time. Expecting dead central to clear rather rapidly near the 12:30pm - 1:30pm (already clear further north) time frame with brisk NW winds to follow and very cool temperatures. Believe afternoon highs will remain in the low-mid 50Fs most areas Central and North.

Do not be fooled by the high temperature forecast you might hear for Sunday. I suspect that temperature will occur very early near sunrise, and only fall through mid-afternoon from the time the front blasts through.
Sunday night lows in the low 50Fs immediate coast to mid-upper 40Fs inland and north as winds decrease overnight, but all in all it seems that temperatures far east central will fall then level off during the late afternoon and remain so through the night.

MONDAY: Much drier, sunny with light north winds and highs back toward the upper 60Fs to low 70Fs South but starting off very cool (mid 40Fs - mid 50Fs A1A corridor Canaveral and south). That was quick. A slightly elevated secondary boundary (part of that big storm system to the north) will skim by Monday night and with that passage and high pressure building rapidly behind it from the west north of the state winds to become NE by Tuesday morning and strengthen by mid to late morning. Thus end'eth any cold spell. 

TUESDAY-THURSDAY: At this point, guidance continues to build mounting high pressure to the north then northeast of the state with onshore winds continuing all 24 hours of day from the ENE-E by later Wednesday . 

Very 'temperate' temperatures near the cool ocean waters with little variation between day and night ...but warmer toward the west coast. Slight chance of light rain mainly east 1/2 of state if not only east of I95  late Tuesday and all of Wednesday.

BEYOND: Big discrepancy in morning model run from before. 

Previous runs showed this strong high pressure to hold tight for nearly one week with onshore winds continuing and a chance of clouds/showers. The latest run, however, brings another cold front toward Friday with a good rain chance. Ironically, though, it then commences with a similar weather pattern of strong onshore winds once again shortly after its passage. Thus, either way. it appears that from Over Night Saturday through all of next week at least we will be in for a bit of a 'atmospheric culture shock' in terms of how it will NOT be anything like the past few days have been. Good news though, little in cold air except for Sunday and then a few mornings west of I95 and toward the far interior and west side. 

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Thursday, March 1, 2012

Warm Through Saturday, Isolated Showers Possible

In Green is where isolated showers 'could' occur today ( already in progress toward SE Florida late this morning) although quite small in stature. More details follow below. In Orange is where a rumble just might be heard after 3:30pm -9pm if a slight seabreeze can manifest and remain east of or near US1. This chance (of thunder) looks very remote however.
TODAY:  Frontal boundary manifesting toward the East Central Plains to move through the Ohio/Mississippi River Valley Basins tomorrow with more severe weather likely, as relayed in the previous post. This system (tomorrow) to the north of Florida will not be the last to impact areas near and east of the Mississippi River in this first week of March (one more to follow ). The early morning image taken from the Storm Prediction Center (SPC) website shows where those experts are watching in terms of severity coverage:

SPC Example from early day today. The next version to come out  later today will likely differ but the threat is clear. Many areas that were hit by severe weather toward Kentucky and through Southern Ill/Indiana could be hit again tomorrow.  
OTHERWISE - Locally. SW wind today with sunny to partly cloudy skies will result in warm temperatures in the low-mid 80Fs with upper 80Fs possible toward East Central interior. Winds just above the deck are also SW, but not so strong that a weak seabreeze could form but remain very close to the coast during to just after peak heating hours between 1-2:30pm. It appears that although no model shows an easterly component wind, they might not be considering the density of the cold air just above the cool ocean waters at this time of year. Thus, a sea breeze could manifest, but likely remain east of US1 or I95. Possible showers especially later should the sea breeze manifest. The first image shows possible thunder in orange, but if so this will likely be limited to one or two heavier showers assuming they can manifest at all. The fact that showers are already occurring toward Eastern South Central and Southeast sections and that showers manifested yesterday toward interior and eastern sections yesterday (later in the day)...should be at least construed as a potential harbinger for late day activity as noted above.  

TOMORROW-SATURDAY: With each day the chance of a sea breeze developing becomes less likely (especially on Saturday) as the storm system's frontal boundary approaches and pressure gradient southwest winds increase. Would not be surprised to see low 90Fs readings eastern portions of Central and South Central , especially on Saturday with near zero chance of rain that day (and no sea breeze). The far east coast, especially the barrier islands have a propensity to 'overshoot the high temperature forecast mark' on a solid "SW wind day" as we enter March. This winter was not horribly cold for any long duration, and even short duration cold spells were rather rare, thus water temperatures are not as cold this time of year as they were last year during the same time frame (early March).

SUNDAY: Change begins and to last through most of next week. Phase one of the change will  be the cold front now indicated to pass from North Florida beginning Saturday to reach Central very close to sunrise give or take 2-3 hours either side of the Central Dividing Line running east - west from SR 528 and West toward Tampa. Most precipitation will occur right along the boundary and behind it due to some over-running. The GFS could well be playing out the high temperatures behind the front in too extreme a  'cold' fashion as is often the case with this model, considering it showed overnight that highs will never make it out of the low-mid 50Fs on Sunday after a warm early start to the day near sunrise to mid-morning. The NAM is much less aggressive and in opposition depicts highs in the 60Fs on Sunday. I suspect the high temperature on Sunday WILL occur prior to 8AM Central either way. Not ready to take a leap either way at this point as to how cool the afternoon temperature will end up at this conjuncture; either way, Sunday stands to be at least cloudy with light showers possible through noon toward 2pm, with high clouds clearing slowly toward late afternoon. South Florida remains "prefrontal' until early afternoon, so more convective type showers and maybe thunder possible portions of South Central and South through 4pm (Keys) at most. Showers are the more likely mode, and much later to ever clear prior to sunset.

Otherwise, very cool to cool all day Sunday with a breezy NW wind slowly dwindling toward sunset and overnight, although not completely.

MONDAY: NNW-N winds and continued cooler with highs in the mid/upper 60Fs to near low 70Fs, mainly South Central/South. Scantily Partly cloudy.

TUESDAY- FRIDAY (at least): A secondary front just above the deck near 2000 ft will complete the transaction of the entire system's (well to the north) passage,  and bring winds around to NNE-ENE during the day on Tuesday. Thus ends the cool spell with very temperate ( very little) variations between overnight lows and daytime highs (especially near the coast) with a steady and breezy onshore flow taking control. 

This flow will be rather moist in a shallow layer, and it appears now extensive low-mid level clouds could be in the offing, as well as showers near the coast most likely beginning Tuesday afternoon through at least Saturday. Thus, much of next week looks less than ideal as opposed to this week currently in progress of drawing to a close.    

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