Tricky 8-Hour Forecast Today, Next Rain Chance Thursday

Image: Contrail from yesterday's Atlas V Launch. Skies cleared as expected in yesterday's post and winds were within the threshold to meet launch criteria as we know now. Surprised the contrail for this launch was so 'wimpy' considering that a 5000ft cloud deck had just cleared the pads area less than an hour before, so moisture was there. Contrail seemed to form, based on the sounding, where the atmosphere was the most dry.

TODAY: Scrambling this morning to make heads/tails of recent evolution of events since 7AM. As noted yesterday, the cold front shown in the image below still well out in the Gulf of Mexico this hour would be preceded by a pre-frontal trough to cross the East side of the state around the 1-3pm time frame. Surface winds after day break were to  veer to SW by late morning, and skies would be mostly cloudy. In fact, they did shift somewhat earlier prior to the area of rain showers that passed earlier this morning, but have backed to south or even SSE in some locations once again.


Some form of a pre-frontal trough evolved early and raced across the state at 70mph as the main storm system well to the north of Florida continues to lift away. Believe this event was associated with the main storm features / upper support pulling away.  This boundary was accompanied by some rain showers, one of which I watched race from Polk County to the coast near Cape Canaveral in about one hour's time. Was this the pre-frontal trough (if there is every going to be one at all?).  Winds behind this boundary continue to remain from the South (even SSE some locations) all the way over to the west side of the state after becoming SSW earlier this morning, meaning that either (A): More significant activity could be in the works for the hatched area shown in the image below later today as another pre-frontal trough forms along the region of lower pressures shown over West Central Florida in the image below, or; (B) All activity will await the actual front and be weak; OR (C) neither of these cases with near no activity anywhere across the state with a dry frontal passage. These seems unlikely.


MODEL DISCUSSION: In watching local WRF model runs and comparing to the NAM, GFS, and RUC it is plain that none of the models agree when it comes to the precipitation fields which is what today's post is pretty much all about, especially in light of the fires over all parts of Florida during the past week (there are many more fires than have made the 'headlines").  In other words, all areas could use some rain.  The RUC has been consistent with showing the bulk of the rains to occur over the East Side of the state south of Brevard county, in other words, SE Florida. On the other hand, local WRF runs are showing the bulk over East Central Florida where I've drawn the lavender hatching, with nearly nothing over South Florida other than some scattered showers near the coast. Very little north of  Daytona / Ormond Beach and western portions of North Central Florida.  However, latest RUC as I just peaked, is starting to share the wealthy just about everywhere. The NAM falls somewhere in between the two, but the GFS seemed to have a handle on the situation as of last night (and continues to remain the most consistent) that would match the local WRF run. So I am running with that, which happens to be the best case scenario for rains over Iron Horse (which by the way, last I saw is now 95% contained).

FORECAST: Clouds this morning, per visible satellite loops, should clear some over East Central from west to east between 11AM -2PM. Winds to remain primarily from the South to SSW (SSE southeast Florida).  Could see another pre-frontal trough develop near that area of low pressure shown on this map over West Central. However, this anomalous area of low pressure has been showing up every afternoon the past few days (oddly). Only difference today is that it popped quite early, normally reserved for the afternoon hours/thermally induced. Highs today under clouds in the low-mid 70s, upper 70s where clouds break more, and some low 80s South Florida, away from the coasts.

Best chance of rains will be from 12pm through 5pm spreading from West to east. If the WRF model is to verify, we'll have to see a broken line of showers developing in about 2 hours from now (or after noon time) on the west side of the state which will move east and strengthen once it reaches that area shown in purple above. This broken line of showers with embedded lightning (possibly) will progress east and south through the afternoon, never making it much further south than Ft. Pierce. SE Florida could see showers just about anytime toward noon and beyond, but is never impacted by the more organized activity further north.  Best chance of a thunder storm or heavier rain showers, again, in the purple area. All models agree that Central Brevard will have decent values of CAPE today no matter which model one looks at.  But the models do disagree overall of where the majority of this will exist which is important for storm sustenance.  

The other thing to consider is that the best wind fields will be from the Beach Line - Orlando - I/4 line and north, whereas the best instability will be further south.  Additionally, these 'best winds' are in the process of pulling off and away as I write, well before peak afternoon heating/instability time. 

This is the case time and time again, not only this year but others as well.  Storm systems this time of year are making weaker passes at the state in general, and lifting the strongest winds fields to the north of South Central and South Florida, leaving this area without the benefit of at least a high shear/low CAPE environment conducive for heavier rainfall, with just enough instability to generate rain showers. No matter how one slices the pie, once one gets north of Daytona/Ormond Beach the rain chances wane greatly.

So in a nut shell, expecting rain showers just about anytime from noon and beyond SE Florida. Maybe some heavier activity/thunder just off the coast later this afternoon. Best chance of rain/thunder East Central beginning 12-1pm in the area shown above, spreading west to east. Rain chances end all areas between 7-8pm, assuming they manifest at all. Keep the umbrella handy if heading out today, just in case. 

Any heavy rain shower or thunder could contain a very brief period of gusty winds of 40-45mph immediately preceding and during initial onset of rainfall. Again, assuming they occur.  WRF at this point is hopeful thinking in regards to rainfall right over what is left of the fire most inappropriately dubbed "Iron Horse". Be real, an official names a fire after where he CAN'T go to party during Bike Week. "Duh-Winning!". What a troll.

Atlas Launch Chances Look Improved, Strong Storms Possible Sunday

Image shows the location of LC41, from which today's  launch of the OTV at 4:09pm is scheduled. Official forecast is calling for predominant favorable sky conditions, with the chance of an intermittent broken deck at 5000 ft. More on this in the the discussion below.

TODAY: Full latitudinal surface trough/cold front progressing through the Deep South late this morning. Tornado Watch box has been issued for parts of Southern Louisiana, Mississippi, and SW Alabama in advance of the boundary. This front will be affecting the Panhandle tonight and the remainder of the state working into early tomorrow morning through sunset (South Central/South Florida) and clearing the state by sunrise Monday with lingering affects far SE Florida/Keys. See image below for a forecast for 1pm tomorrow.


LOCALLY: Atlas V launch scheduled for today. Only factor that would preclude launch now it appears would be winds, which don't look strong enough/nor will be/ to hinder.  Forecast concern is a deck of 5000 Ft level clouds conducive for triggered lightning. But as it appears now, with a good deck of cirrus moving overhead as I type to last into peak heating (early afternoon), this deck will not be able materialize. Any clouds trying to form over the Gulf Stream to be advected toward the coast decay as they slide under the cirrus deck.

Also, any rain showers well offshore are petering out as they approach the East Central Coast as they run under the cirrus deck.  Surface winds at launch should be East to ESE at 12-18mph, gusting to 23mph.  As I type now, the latest observations along False Cape and the landing strip have winds gusting to the 21mph range. Is that too strong? That is not the official forecast, just my line of thinking. As such, believe the launch should be able to go, but bears watching in regards to wind. In any case, looks better than yesterday as of 11am.  We can see the pad from which it will launch is a bit further south of the Shuttle Launch pads per the image above.  The actual vehicle being launched looks for similar in shape to the shuttle, just smaller.

SUNDAY: Winds tonight to die down late night and shift from SE-SSE-S by daybreak. Mild overnight temperatures in the low-mid 60s under partly cloudy skies as some strong storms enter the Panhandle and progress eastward toward the Tallahassee region.  Day break over Central should yield to partly cloudy skies South Central/South Florida to near mostly cloudy far NW North Central. Winds S-SSW at 15mph, gusts to 22mph by midmornign.  Slight chance of showers with increasing mid-upper level clouds.


By late morning one of two weak pre-frontal boundaries will cross Central, perhaps accompanied by a rain shower.  The stronger trough will enter and cross  eastern portions of North Central and East Central Proper (from roughly the Pineda Cswy to Sarasota and points north between 11:30am - 3pm time frame.  During this time a 250mb jet streak is forecast to pass directly over Central Florida providing a lifting mechanism. Additionally, this will occur during peak heating, albeit offset/precluded of greater instability by early day clouds.  Winds with height become increasingly unidirectional working into the afternoon hours, but they do increase namely along and north of the Beach Line - I4/Tampa. line.  Could see a slight sea-breeze as well  further south along the coast as far north as Sebastian/Melbourne Beach area.  Actual cold front does not cross the East Side of the state until near to just after dark. Temperatures aloft tomorrow will be cold with 500mb forecasts showing -15C and 700mb showing 0C.  If this were a summer day, we'd be talking about severe storm likelihoods with those numbers (considering the surface temperature would be in the 90Fs).  Below is a forecast for 1pm EDT tomorrow. Orange areas are weak troughs preceding the front which will take all afternoon to cross the state. The parent surface low near Virginia will be moving NNE nearly paralleling the coast.

However, this is not summer. Expect highs tomorrow, assuming there will be increasing clouds spreading from west to east during the time of heating, to only be in the upper 70Fs, warmer South Central and South with some low 80s SE Florida.  Still, hard to ignore the jet stream streak winds, moderate instability, and weak convergence along the surface boundary, especially right at the coast from Cape Canaveral to Melbourne Beach (especially if a sea breeze develops).  


With this said, believe strong storms are possible all of North Central north of the Beachline from North Tampa Bay east to Oakhill, with better chances the further north one goes.  Slightly less likely chances north of a line from Sarasota to Sebastian Inlet. Immediate East Coast from Daytona to Sebastian between 11AM to 4:00pm (south end). We can iron out the details early tomorrow in regard to timing, and/or the reference to strong storm potential. The "strong' part would be in the form of wind gusts of 40-48mph and tiny hail. And maybe a brief/weak 'spin-up' tornado east of I-95 from Cocoa Beach - Sebastian (however, this chance is close to entirely nil as of this writing).


Further south toward southern South Central to SE Florida will experience convective showers with thunder possible as well, particularly from near Boyton Beach south to Miami along the East Coast beginning mid afternoon through dark. But activity there should be below the 'strong' threshold due to the timing of the boundary entering this area close to, if not after, dark, as well as that fact the mid-upper level winds of substantial strength will be pulling off to the north and east of this area after having crossed Central Florida before the surface boundary (s) arrive down there.


MONDAY: Pleasant day at hand post-front. Temperatures comfortable in the mid-upper 70s. NW winds veering to NNE east late. Could get smoky smelling over much of Brevard due to 'Iron Horse'.

Will The Atlas V 501 (OTV FLT 2) Launch Today At 3:50 EST

Image: Video Grab taken from my Cape Canaveral location of a prior Delta Launch.
March 4 @ 3:50 pm - Atlas 5 - OTV (X-37B). The Launch Team is continuing their operations toward a 3:50 pm launch. According to the 45th SW Weather Squad, there is a 70% chance the weather will be unacceptable for launch. The primary concerns are gusty Ground Winds and Cumulus Clouds. 
See this link for a live simulcast access to launch 25 minutes prior to launch: http://www.ulalaunch.com/site/default.shtml
ANOTHER LAUNCH ALSO SCHEDULED FOR NEXT FRIDAY: March 11 - Delta 4 - NROL-27


TODAY: As you might have read above, the restricting factors for launch today are clouds, but probably of more greatest assuredness are the gusty winds.  Winds at this hour are from the east gusting to 22mph. with a rain shower. Here's is a photo (just taken) of what this low topped rain shower looked like from near Port Canaveral looking north toward the pad. Acutally, it had probably moved beyond the pads area by this time.  See radar image further below.

So, again, whehre will the clouds be  around launch time and will there be too many ? Maybe, maybe not. They are not a constant, with some very good breaks between the surges of them and rain showers. So timing will be of the essence. What about the wind? Could be close as well. I do not know what the exact threshold is for winds. It can vary from launch to launch regarding both speed and direction from which it blows for certain missions, although I do not know if this applies to unique Atlas launches. But as reads above, I'm assuming the 70% no-go is based on winds primarily, since that forecast was made well before the scope of rain shower activity was known.


OTHERWISE: No changes from yesterday's post regarding upcoming days. Winds generally easterly today at 12-18mph with gusts to 28mph. Rain showers possible, widely sporadic.


TONIGHT: No change, but winds will abate a little at the coast, more so inland. Coastal lows (A1A) in the mid-60s, low 60s/ upper 50Fs further inland. Better chance of showers from Canaveral and north to Jacksonville later today and through the evening.


SATURDAY: Few changea as wind gradually veers to ESE-SE very late in the day with light rain showers possible.


SATURDAY NIGHT/SUNDAY: Winds veer to south over night and decrease, then pick up after sunrise from the SSW-SW by noon as a pre-frontal trough / cold front couplet approaches from the WNW.  Rain chances increase by early morning spreading from west to east across North and North Central Florida...roughly along and north of SR 528 / I4 / Tampa.  


Highs in the mid-upper 70Fs, cooler further north to precedent cloud coverage. Very small chance of thunder after noon, with most likelihood along and north of I-4. Shower chances end from north to south / west to east shortly after sunset.  Rain chances end South Florida by early evening.  Winds shift to NW - N -NNW going into Monday morning.


IRON HORSE: Last I can find, the blaze is only slightly more than 25% contained, solid as a rock (iron ore). Probably has changed some by now.  Some showers did pass close to the burn today, so that may have helped matters somewhat, but they were far from 'drenching'. Some showers are passing just south of the burn as I post.

 One of the big concerns with this wind is if any lit ambers were to get lofted toward a fresh/unburned area nearby only to ignite another blaze. Smoke will continue to advect upstream per wind directions, and as alluded to yesterday...it might be the area SSE-S of the blaze (most of Brevard) that will bear the brunt of the exhaust by early Monday morning.  Next chance of rain arrives sometime on Thursday or very early Friday.

Will "Iron Horse" Smoke/Smell Meet It's Namesake Sunday?

To the left is an image of the location of the Iron Horse Saloon north of Daytona Beach as annotated. The yellow area sketched in is where smoke and/or smell could become an issue on Sunday from Sunrise to early afternoon. Arrows show the expected shift in surface winds from sunrise through 3pm. The following image is a forecast generated by the North American Model (NAM) this morning for Sunday afternoon.

We can see from this forecast image that surface winds overnight Saturday into Sunday morning will shift from SSE to SSW-SW. The net affect would be to advect the smoke and/or smell

from the Iron Horse Blaze location toward the Saloon.

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Again, above we see the forecast per the NAM for Sunday at 1pm. SSW winds of 20mph are forecast to develop with daytime heating ahead of the pre-frontal trough. These will gradually become more SW to finally NW overnight going into Monday.  HOWEVER, there could be a saving grace for North Volusia County/Southern Flagler. Rain chances go up during the course of the wind shift. See more below in the detailed forecast discussion.

TODAY: Continued easterly fetch. with embedded bands of enhanced cloudiness, and perhaps some very light spurts of rain in the worst cases. Any showers to impact land will be very brief and light with the quick flow indicated at steering level aloft. This image above was just now saved from the web site called "weathertap". It is totally overcast as I type as that small 'green' area by the Cape is passing overhead. Other areas of similar conditions, which might have some trace rain are moving ashore, and this will continue to be the case this afternoon. For the most part skies will be partly cloudy, with east winds gusting to 22-28mph at the beaches (east coast). Highs in the mid-upper 70s, warmer interior and west.

TONIGHT/FRIDAY: Similar situation for today with no measurable rainfall expected. Wind not as strong late night through early morning, but do expect winds to again be breezy on Friday.

SATURDAY: Winds will become more SE-SSE during the day, possibly stronger than today. A cold front will be approaching the state. At this time the smoky stench from "Iron Horse", whether or not it is still burning, will be advected toward Deltona/Deland/Sanford/Osteen areas. However, rain chances also pick up for the coast and the burned/burning area beginning later Friday through much of Saturday from Cocoa Beach and north. It might be just enough rain to appease the flames, but could actually make the smoke/scent situation worse for folks close to and upstream of the blaze as the particulates will be closer to the ground. I'm definitely not a fire weather/particulates forecaster, so this is just a heads up from what little I do know.

SATURDAY NIGHT/SUNDAY: Winds overnight Saturday into Sunday should let up after midnight to early Sunday. At this time the vector points toward the "Iron Horse Saloon". Again, will it have rained enough, if at all, to prevent the vapors/smoke from reaching that far NNE? If it doesn't rain, could get pretty crummy even that far north. Especially since winds will really die down overnight Saturday night. Could get really nasty around Edgewater north toward "Wilbur-By-The-Sea".  Otherwise, expecting increased cloudiness at day break over all of North Central Florida, decreasing further South as one gets south of Brevard/Osceola Counties.  High temperatures in the upper 70s, with lowers 80Fs far South Central/South Florida.

SUNDAY AFTERNOON/EVENING: Latest NAM/GFS have indicated a frontal passage sometime Sunday night, and this continues to be the case. The only fly in the ointment concerns rain chances. Could be raining as soon as mid-morning for the east side of the state north of Melbourne Beach between the eastward advancing pre-frontal trough and the retracting high pressure area over the Atlantic that will have been generating all this wind today through Friday.  

Due to the time of arrival of the pre-frontal trough (peak heating hours), some of these rains 

could translate to thunderstorms (weak).  Guidance shows little in thermal instablitiy, but there is some shearing as well as more mixing due to voriticity both in the lower/upper levels of the atmosphere than I've seen in sync with a surface boundary than I've seen with previous systems. The impacting values are pretty weak, but the sum total of them all could result in a storm with thunder.

SUNDAY NIGHT: Probably our best chance of rain North and North Central will be associated with the pre-frontal trough, and not the front itself, although rain (but not thunder) could still occur until the front has cleared this region. Do believe the percentage of the region of North Central Florida up to Jacsonville to receive measurable rain from the period beginning late Sunday morning through evening will be about 70%.  It won't be raining that entire time by any means. That number just reflects total possible recipients over the entire time frame.

Further south toward Southern Portions of South Central and South East Florida (or roughly from Sebastian Inlet to Miami), rain/thunder chances are notably smaller. However, SE Florida from Boyton Beach to Miami might get convective type showers Sunday afternoon indirectly related to the pre-frontal trough as well as with the front. Not sure the pre-frontal trough will ever reach any further south with an impact other than a wind shift from SW to W south of Vero Beach.

MONDAY AFTERNOON: Will tackle this time frame tomorrow. But for the most part this system will have cleared the state, or be dwindling in some form or another over far south Florida where a rain chance will linger on the SW side of the state. No big temperature changes at all, if any, from recent days after the period of abnormal warmth ended the other day.  And lastly, if rains don't add up enough (although I highly expect they will)...could smell kind of smoky for the north half of Brevard County on Monday.

Persistent Onshore Flow East Coast Through Friday

For today post, please see the link below. Rather than writing out a long 'winded' discussion today. This sums it up.  Thank you accu-weather. Small craft and rip current advisories almost guaranteed. Water temperatures might be getting warmer, particularly south of Ft. Pierce, but watch the rip currents if venturing in the water through Saturday.

Only thing to add is rain/temperatures:


Warmest overnights South Central / South Florida east coast with lows in the upper 60s/low 70s. Coolest west side.


Highs in the mid 70s, some upper 70s west side, coolest NE Coast. Rain chances slim, but most likely along the east coast (particularly Thursday from the Cape to Jacksonville.


Winds will become more easterly Thursday to ESE Friday and SE-SSE Saturday. Rain chances almost nil after Friday.

http://www.accuweather.com/blogs/news/story/46441/dangers-lurk-for-florida-east.asp

"Black Monday" Severe Weather Reports Filter In, Florida Warm and Breezy

Image: Above is the current depiction of severe weather related storm reports, some preliminary, as of noon Eastern Time on this "Black Monday", February 28th since yesterday. So far there has been 219 total reports of which 153 are wind related, 61 hail related, and 5 tornado related. Not visible underneath the blanket of reports is a few funnel cloud reports. *Note the Tornado Icon near northern Oklahoma (not placed exactly correctly in this image).  Also shown is the official risk areas today in the shaded area through 7AM EST Tuesday morning. The shading in Central Florida is for a risk of general thunder, with higher risk along I-10. Not shown in the image above is flooding related activity.

*Here  is an image from yesterday while activity was just getting underway in the Southern Plains. It shows the risk areas at that time from General to Moderate (in red). Over Kansas we can see (upon enlargement) a storm showing on radar. The little icons of vehicles are storm pursuers who have GPS/software enabled programs running through on-board laptop computers and have them in the "on" (detectable) position. Note how they are clustered near the storm that eventually produced a tornado as indicated in the first image. We can even see the identify of these folks via the inset to the right.


CENTRAL FLORIDA WEATHER TODAY: Breezy and warm. S-SSW winds 15-22 mph, gusts to 28 mph. The cold front is moving through the Deep South as I write. Several Tornado Watch boxes are in place at this time, and during the day these will be dropped with others being issued further to the east (or Severe Thunderstorm Watches) as the front progresses toward the coast. In fact, I'm hearing about tornado warnings in Tennessee at this very moment. So what the heck, here's what radar looks like in Tennessee at the time of these warnings. Note also the storms forming in Southwest Alabama. One of those could go severe (in my opinion).

But in Florida it will be very warm with highs in the low-mid 80s, much like yesterday.  Might be a few spotty upper 80s as well anywhere in the interior. Temperatures right near the coast might only make it to the 79-81F level along either coast. Expect a near side shore component to the wind along the East Coast today, more to onshore south of Ft. Pierce and around Canaveral Bight south toward Indian Harbor Beach. No rain under widely scattered clouds, becoming nearly clear some locations at times.


TONIGHT: The tail end of the rapidly weakening southern end of the storm system will move through Northwest Florida as the main parent low passes by Maine. Some heavy snow is expected up there with totals up to or maybe over 8" with very breezy winds to boot.   You can see the location of where the main low will be by 1pm EST in the image below near Maine. Winds over night will be lighter from the SW-WSW with lows mainly in the low-mid 60s with upper 60s along the coast and some low 70s SE Florida coast.


TUESDAY: Front will enter North Central Florida at day break and pass through that region between the hours of 7AM-1PM. Accompanying the boundary will be some light rain showers and a wind shift to the northwest.

By 1pm the boundary will roughly be located as shown here, or in other words, it will be entering South Central Florida.  At about this point the front will have nearly completely decoupled from any remaining upper level support (if not entirely) and frontolysis will be underway, but there will be ample moisture for the continued chance of rain showers over East Central Florida mainly from 10AM further  through 2pm as one goes south. Do not expect any thunderstorms anywhere south of St. Augustine (although the first graphic showed that will be the case).  The Storm Prediction Center has all of South Central and SE Florida in a chance of thunderstorms tomorrow, however believe that was mainly predicated upon the assumption there would be a sea breeze collision boundary against the predominant SW winds, however it is very unlikely a sea breeze will ever manifest, this no collision and no thunderstorms. Given there would be no other driving factors to contribute to thunderstorms other than weak thermal instability, I'm dropping them from the 'unofficial' post. If there's to be any thunder tomorrow believe it would be near West Palm later in the afternoon.  

As we see in the included image, I've drawn the front in as 'breaking up' with a weak stationary boundary generated, in part, off a thermally induced surface low within the warm waters of the Loop Current in the Gulf.   A portion of this low could simply relocate during/after peak heating to just off the coast of Ft. Lauderdale late in the date as high pressure builds south. 


By Wednesday afternoon whatever remain of either boundary will be just south of the Keys.  Rain showers will be possible as well further south along the east side of the state and over the Keys.


Once all is said and done with this portion of today's forecast post (through tomorrow night), rainfall totals will range from a Trace to perhaps 0.25" (quarter of an inch). Believe any 'true' thunder to occur would be just offshore the east coast of Boyton Beach to Miami. There is a sparse chance of a renegade rain shower from the Cape and South through midnight, Tuesday night though as a tongue of upper level energy will ride over Central Florida possibly re-manifesting a shower at some point.


WEDNESDAY: Winds will shift from NW to ENE by Wednesday morning just about everywhere except extreme South Florida will the boundary will have yet to clear.  Temperatures on Wednesday will be in the mid 70s to near 80F on the west side of the state under partly cloudy skies, possibly mostly cloudy SE Florida where low end rain chances remain, perhaps a better chance SW Florida.


THURSDAY-SATURDAY: Brisk East Winds becoming ESE-SE by Saturday and picking up gradually through the time frame. Highs in the mid-upper 70s and lows in the mid-upper 60s, cooler far inland and west Florida.


NEXT BEST CHANCE OF RAIN: Perhaps Saturday, but more likely Sunday sometime. Thunder might be included in this time frame as well.  But per the long range run of the GFS model, the next couple of fronts to impact Florida will do so in similar fashion as the one tomorrow will, with the state getting only the remnant sloppy seconds (at best) of anything of "dynamic" nature. But still watching the weekend time frame  closely from something "...more than".

"Black Monday" Begins Later Today - Sunshine State Lives Up To Name

Image: Surface plot for 7AM (EST) Monday morning, shows the general placement of surface features at the time. By this time, a tri-modal "Black Monday" (see below) severe weather will be occurring.  The yellow area shows a generalized area of most intense activity/areal coverage with the aqua showing other severe type activity to occur through Monday, spreading east with time.  Not shown is additional flash flooding concerns in South East Ohio, parts of Kentucky, Indiana, and Pennsylvania (to name a few).

TODAY: High pressure will reign supreme today as the last of yesterday's surface features which layed dormant overnight are quickly eroding during the first hours of daylight. All upper level support for any feature other than the high pressure ridge axis shown in this image exited during the wee hours.

This afternoon will be warm and sunny. Coolest temperatures in the upper 70s will be found primarily within 1 mile of any coast due to light afternoon sea breezes, quickly warming as one heads toward the interior into the low-mid 80s. Warmest temperatures by mid-afternoon will be located in general within the bounds of the yellow area I've sketched in. Coastal temperatures south of North Central and Northwest Florida will not be as greatly effected as they were earlier this month  (in the cool sense) due to warming sea surface temperatures the past 10 days. For example, the temperature at the Cocoa Beach pier has warmed from the lower 60s to 70F. The temperatures off Daytona have warmed into the low to mid-60s from the mid-upper 50s as well. Last to warm will likely be those offshore the coast of St. Augustine to JAX and perhaps along the Panhandle Coast.  Inland lakes, including Okeechobee have also warmed notably since those of  early and mid-month readings.


Winds today over the South half of the state will be primarily from the SE once the diurnal heating/temperature cycle is fully in place. No rain today with less clouds, some locations may barely see a cloud at all.


TONIGHT/MONDAY: Winds become near calm overnight, with a few patches of shallow inland fog. Lows in the low-mid 60s many locations, with a few upper 50s well inland north of Lake Okeechobee and North Florida.  Afternoon temperatures will be warmer all locations on the east side of the state than today, reaching into the low 80Fs. Winds will be generally from the South at 10-18mph during the afternoon, but gain a bit of a more onshore component during the afternoon which could take coastal temperatures back down to the upper 70s with a few more cumulus expected inland as high pressure relaxes a bit to the east and south preceding the approach of the approaching storm system 'complex' towards the U.S. Coast, primarily from Eastern Georgia to New York.


Meanwhile, a  complex Tri-Modal  synoptic scale configuration of a variety of atmospheric conditions consisting of at least two or three low pressure systems, a warm front, cold front, and dry line (initially)  will create areas of combined directional/speed shearing wind profiles and thermal/moisture gradients, just to name a few to generate storm modes ranging from flat out long duration heavy rains to a QLCS type squall line (primarily the south portion originally) to more isolated, discrete rotating thunderstorm structures which will  spread east with time. The QLCS is essentially a 'mixed mode' line of embedded discrete cells with bowing line segments, rather than a flat out linear squall line. Backbuilding storm cells (that is to say, regeneration of newer storm activity following intial storms) after the first severe weather threat has passed, could re-initiate in the area just along and south of where the warm front is located particularily over NE Arksansas, West Tennesse, SW Kentucky, and Southern Illinois. 


There is a moderate risk of severe weather associated with this said scenario as discussed by the Storm Prediction Center (SPC) embedded within a very large area of slight risk which will expand with time toward the U.S. East Coast.  Florida is not included in any of this activity though, at least not in the 'severe' weather sense at any time. Strong tornadoes are possible, most specifically from South Central Arkansas  northeastward to Western Tennessee and extreme SW Kentucky, not to discount other areas where this region will be potentially impacted first by discrete cells and then, after a lull in activity, by the quasi-linear convective system. Other outside areas to watch will be SE Kansas toward Southern Oklahoma (east of I-35).


 And we've only discussed the forecast synoptic scale features. Within those features will be the mesoscale boundaries/nuances that will evolve/activate beyond the scope of any forecast other than  short short or real-time releases.


Local weather offices and media services are all handling their area of interest and will be issuing the proper watches/warnings/alerts as the activity unfolds.  This severe weather event will likely be much more significant than the event which occurred  just a few days ago as was expected would be the case in the post written a few days ago.  Recall, there was over 200 severe weather reports with the last system. Believe this go around we might be able to double that number, namely in the wind damage report category.  Outside of the risk of tornadoes (some could be strong, long tracking) and winds, flash flooding will be a big concern in those areas that already have estuaries nearly full from last week.  The only  fatalities from last weeks severe weather event were caused  indirectly by drowning (Arkansas).


TUESDAY: Last of "Black Monday" will be offshore or nearly so in regards to severe thunderstorms by afternoon, although the areas of flood potential will remain in part of the Ohio Valley and South half of Pennsyslvania.  The cold front  will extend across North Central Florida and will cross Central proper between 11am - 2pm.  During/after this time the surface features will start to decouple from the upper level support.  By sunset the front should be as far south as somewhere between Vero Beach-Ft Pierce on the east side.  After dark through sunrise Wednesday the remnants will sneak through South Florida to be located along or even south of the Florida Straits by mid-afternoon.


Best chance of rain with the front will over North Central Florida and eastern portions of South Central from 10AM - sunset, working south with time.  Still giving us a 30/40% chance of rain during this time as was posted two days ago, but some places already have a 100% chance of rain (at any one given location), we just don't know exactly where those location will be.  


Hedging at looking at all of South half Volusia, Brevard, Seminole, Indian River, and St. Lucie County continuing south to the north half of Palm Beach county when all is said and done overnight Tuesday night.  Only difference in thinking is to take out thunder chances altogether, although will leave in a 10% chance of a rumble from 11AM - 3PM from Sanford south to Sebastian and inland toward eastern Orange County and Osceola County.  Only because of the timing of the boundary passing during peak heating.  But even that appears is a stretch (for thunder) given there will be close to nil instability due to lack of insolation (preceding cloud cover) and weak wind profiles as the system decouples.


WEDNESDAY-FRIDAY: Winds will be NE-ENE almost immediately following frontal passage. Long term ENE-ESE winds will follow during this time frame, with a long fetch off the Atlantic. Prolonged onshore flow could generate coastal showers first over SE Florida then working to Central and North Central Coasts on Thursday/Friday. High in the 70s, lows in the 60s and a rip current threat for the entire East Florida coastline.


BEYOND: Next system will approach 'sometime' next weekend or beyond. There is large disagreement with model guidance regarding the next storm system. The trend of the GFS has been showing a much more dynamic system though (at least in the past 24 hours worth of model runs), so it bears watching.

Very Pleasant and Warm South Central and South

TODAY: As we you see, we are dealing somewhat with two boundaries this Saturday morning. The first image shows where 'technically in one sense" what remains of the cold front that impact much of the Eastern portions of the country lies across North Florida. However, on the southern fringes of the strongest mid and upper level winds aloft there lies a moisture gradient (along with a few others) defining a secondary stationary boundary across dead Central Florida at 9AM this morning.  Any weather to occur over Florida of cloud or light shower nature will be along and north of this boundary (and south of the more northern one).

s we can see, we are dealing somewhat with two boundaries this Saturday morning. The first image shows where 'technically in one sense" what remains of the cold front that impact much of the Eastern portions of the country lies across North Florida. However, on the southern fringes of the strongest mid and upper level winds aloft there lies a moisture gradient (along with a few others) defining a secondary stationary boundary across dead Central Florida at 9AM this morning.  Any weather to occur over Florida of cloud or light shower nature will be along and north of this boundary (and south of the more northern one).

In this image we see where Suface Moisture Flux Divergence (Low level Moisture Convergence) is occurring along the 'weather making' boundary. Very little will change with this configuration today

This image shows that the greatest overall atmospheric moisture through the mid-level reside north of the stationary boundary. Satellite imagery implies there is more than what is shown here. Steering is from west to east of the clouds.

Finally. I'll include the morning visible satellite imagery to show that indeed the greatest amount of cloud coverage is along and north of the boundary where the greatest moisture resides.

I've also drawn in where I believe the warmest temperatures will be today PREDOMINATELY. The large reddish circled area is the 80Fs, with the purple area being mid-80s.  Under the clouds today temperatures will probably struggle to break 80F.  Not shown, is the area north of the cool front in clearing skies. Some spots here might also get close to 80F as well, just to show how weak the overall thermally speaking, actually is.  The coolest areas will be along the coasts within the bounds of the light blue lines.

Also shown in the image above is where the best chance of a sprinkle will exist. Perhaps the best chance of all though by day's end will be that area on the east side of the state.

TO RECAP: Partly cloudy south and south central today south of the stationary front and warm with highs in the low-mid 80s. Along and north of the boundary highs in the upper 70s, and perhaps mid-70s in the coolest areas.  The area along East Central might not receive a sea breeze until after 1 or 2pm, and could warm to 80F before onset of the sea breeze, contingent upon the amount of cloud cover, especially the area in Brevard. But have a feeling clouds will move in shortly to offset that magic mark.

Otherwise, very pleasant with light winds this afternoon, coolest within 1/2 mile of the coasts. Warmest interior South. Slight chance of a light shower as shown above, with the best chance (15%) near SR50 from Sanford to Titusville and into SW Volusia County.

TONIGHT/SUNDAY: Boundary will remain in place until daytime heating tomorrow, or roughly 11AM-1PM.  Winds tomorrow will become ESE-SE by later in the day as the uplift provided by the stronger winds aloft pulls away no longer provided a source of lift in the mid-levels for that cloud deck shown in the satellite image.  For could again be an issue tonight after mid-night through early Sunday where the clouds are no longer an issue. Temperatures on Sunday similar to today, but probably a bit warmer than today where the clouds will have remained most prevalent.  

Otherwise, storm system in the South Central Plains takes shape and begins to impact the east 1/2 of Oklahoma eastward into Southern Missouri, all of Arkansas, and Northern Louisiana, and NW Mississippi. This system's greatest severe weather impacts (in regards to the potential for tornadogenesis) will be near dark Sunday night and overnight into mid-morning Monday as the system en-masse moves east and a bit northward with time toward the Mid-Atlantic and NE states.

MONDAY: Yet another nice day as breezes pick up a notch from the SE-SSE during the afternoon under partly cloudy skies.  The Plains system will have cleared Oklahoma by daybreak, and will impact all of Arkansas in some form or another, eastern Missouri, and Southern Illinois...as well as the west half of Tennessee. There is a very fine corridor of greatest tornado potential during the course of events within a very broad area that the Storm Prediction Center has placed in a "Slight Risk" for severe weather. Believe the initial area will be near Ardmore, Oklahoma (extreme South Central OK) before sunset, but there are a few other locations such as west of Wichita, Kansas as well as NW Missouri to name just a few other 'outliers'. Looks likely that this will primarily be a QLCS event (much like the one the other day)...along the southern extent of the storm complex. Further north such as near N. Missouri, much of Arkansas, and into S. Illinois there will be a great chance for discrete storm cells embedded within otherwise cloudy sky conditions where the greatest helicity (spin potential) will be.  The greatest low level forcing will be further south in the liner mode region, however this area may very well be highly-capped under CIN

TUESDAY: The attendant cold front from the system described above will be across NW Florida and entering North Central Portions at daybreak.  Winds overnight Monday into Tuesday will pick up from the SW over Central Florida particularly overnight. Another muggy, warm for this time of year evening in store with little concerns for fog except maybe over South Florida (interior).  Lows in the mid-60s...maybe even some upper 60s East Central.

The front will reach roughly from Titusville to Tampa around 2-4pm, accompanied by clouds most definitely and showers (still give it a 30/40% chance of rain coverage in beginning late morning through mid-afternoon). I'll give thunder chances a 15% chances namely over East Central Florida from Orlando -Sanford-Oakhill and down the coast to just south of Vero Beach (later in the day) and into the NE Quadrant of Osceola County, and throw in the east side of Orlando for good measure.

TUESDAY NIGHT/WEDNESDAY: From will reach the Miami Metro. Winds central swing around to ENE, but light. Partly cloudy with shower chances from West Palm and South, especially after late morning. But chances of thunder of South Florida appear will be over the interior and SW portion. Very small chances at that.  Still appears the boundary will make it to the Florida Straits by Wednesday night before completely washing out to the east. However, this will be just the beginning of an entirely new weather scenario through the end of the work week.

Only change to yesterday's line of thinking is that perhaps the strongest easterly winds to develop from the Cape to Miami might remain offshore, with the best chances of showers to be along the Treasure Coast to Miami Thursday and Friday. Temperatures will run about normal for afternoon highs, with warmer than normal overnight lows (low-mid 60s A1A, mid-upper 50s interior).

Warm Statewide Today, Breezy Early

Image: Visible satellite image captured after launch of Discovery yesterday shows in the circled area the contrail visible from space. With close inspection one can see the contrail plume in the center of the circle.

RECAP: Storm system that gained much hype in the weather world prior to yesterday continues east toward the Mid-NE Atlantic coast this morning as I type, in a much weakened state. So far there's been 10 tornado reports all in all, but none of them appears to have been a major headline maker. But there was some significant damage reports filtering in. Other than one, all the reports came in from Arkansas and Tennessee, where in Weakley it was reported that tombstones were pulled out of the ground and in Davidson two churches were damaged. "Holy Moses!". There are some reports of rather significant damage but none of 'total destruction'. There was also 202 wind damage reports and 4 of severe category sized hail.

TODAY: The related surface cold front will continue into N. Florida today. Preceding the front clockwise cirulation around high pressure to the east and south of Florida will generate a brisk SW wind late morning through early afternoon, with gusts to 25-28mph possible, but they will weaken by 2-3pm. Some clearing early should give way to a generous portion of afternoon cumulus type clouds this afternoon with the high in East Central Florida perhaps breaking a previous record (at MLB at least). Today's record their is only 84F, and it appears that is easily within reach considering I expect to see widespread low-mid 80s with a few spots in the upper 80s South Central and South. Winds she relax by mid to late afternoon. The only spot that might get a sea breeze will be south of West Palm very late afternoon and only very close to the coast.

TONIGHT: Boundary sinks to near a Daytona Beach to Brooksville line as winds go near calm overnight and becomes stationary while losing all frontal feature integrity. Good bet for some fog tonight over a broad expanse through mid-morning Saturday.

SATURDAY: Other than a scant chance of a spit of rain, and perhaps drizzle under the boundary overnight and early morning, winds will be light with light sea breezes right along both coasts in the afternoon under partly cloudy skies once the clouds/fog break (assuming they materialize). All rain chances gone statewide with another warm day in store (note quite as warm Central), especially over South Florida away from the immediate coast.

SUNDAY: Another foggy start quite possible with light afternoon sea breezes and temperatures running a few degrees above normal, but really nothing different than what we've felt in recent days past. Winds becoming more southeasterly during the course of the afternoon.

MONDAY: Next front will be approaching, SW winds once again accompanied by warmer temperatures across the boards. No rain.

TUESDAY: Front will move through NW Florida overnight and enter North Central Portion at day break with a chance of showers followed by a NW wind shift behind the boundary (quickly becoming NE within 3-6 hours after that point). Front will sink toward South Central Florida by sunset. Best chance of rain (I'll give it a 30/40% chance) will be across East Central Proper from sometime between 11am - 7pm, from north to south with time. Furthest southern extent of these rain chances will be between Ft. Pierce and West Palm by early evening. Could hear a rumble of thunder from Titusvillel south to Ft. Pierce after 1pm on the east side of the state along the front as it passes through. Not expecting thunder at this point far SE Florida.

WEDNESDAY BEYOND: Pattern change in store as front resides along the Florida Straits just south of the Keys and north of Cuba. No big cold surges just as a hint, but could be hearing about coastal small craft advisories/hazardous rip currents by late Tuesday -Friday due to prolonged onshore flow, breezy at times, as well as coastal showers. I stress "Could"...but the pattern seems to be set for a good 3 days of easterlies combined with a shallow but moist onshore flow evolving within this time frame before the next front arrives by late weekend. Might not be so sunny either, perhaps mostly cloudy. No thunderstorms.

Will STS-133 Shuttle Discovery Be Able To Launch Today?

Images: (1) KSC mesonet with launch area circled in lime color. (2) State wide Local Data Integration shows a very weak low pressure circulation just off Canaveral Blight in the lee of of the Gulf Stream where upstream east to eventually SSEasterlies will develop late this afternoon. A few light rain showers are well offshore, and gray/silver lining shows the greatest cloud coverage at this time.

NOW: Morning fog many areas state wide is burning off and skies are completely clear at Canaveral with a light east wind. Subsidence aloft and in the windward side of cool, light onshore flow is scouring out the clouds at KSC, but dew points remain high, at least until early afternoon. The current conditions might be a bit misleading considering that a transition, albeit insignificant outside of a rocket launch concern, is underway. In the image above, we see what has become this season a very weak cyclonic circulation just east of Canaveral Bight formed by weak overnight land breezes , the remaining old frontal boundary, and stronger SE flow trying to develop...all along an inverted coastal trough tracing the west side of the warmer Gulf Stream waters.

TODAY: As high pressure off the coast of South Carolina strengthens a bit and drops south and east a bit in response to today's severe weather maker for parts of "Dixie Alley" (especially from East Central Arkansas to Western Tennessee, NW Mississippi, extreme NE Louisiana, and SW Kenucky) which will be pressing east throughout the afternoon and into the eveing, the coastal trough will wash out as it forced to cross the cooler near shore waters from where it currently resides and toward the Florida East Coast. Light easterlies this afternoon will transition to SSE around launch time blowing around 12-18mph (perhaps gusts to 22mph). As such, do not believe winds will be a factor.

Otherwise, during the transition a light, short lived rain shower could approach the coast, but the likelihood of one to manifest off the cool ocean waters (or survive the journey away from the warm, moisture Gulf stream waters source) seems very low. However, cloudiness of ' partly cloudy' nature is a possibility. Even so, do not think 'triggered lightning' will be a concern today due to very low end convective nature of the cloud types.

Only concern today from the meteorological perspective is whether or not a broken deck will manifest at around 4500 ft. later this afternoon after peak heating. Like mentioned, at this time it's clear as a bell out there, and that may very well end up being the case right up until launch time. But I wouldn't lay 1000 dollars on it. I'd give it a 65% chance of a go, at least right at launch time. If we don't start seeing clouds appear between 3-4pm we probably never well.

Best chance of clouds appearing will be between 4:30pm through 7pm....somewhere within that time frame as the boundary will become absorbed in the averaged SSE flow and spreads any coverged moisture onshore, lasting because a SSE wind blows across warmer ocean waters than one from any northerly component are at this time of year. By the time we reach the waning minutes of daylight clouds should disperse, with significant clearing within 1 hour after dark.

BEYOND TODAY: SSE winds all night will gradually veer to SSW by sunrise Friday. It will even be a little breezy right after sunrise tomorrow, and warm all along the East Coast, especially north Vero Beach. Highs in the mid-80s, and a few spots of upper 80Fs. Melbourne's record high temperature for the date might again be jeopardized for the 3rd time this month, but probably won't be broken since I think the record high for the date is something like 90F (at least). Not sure, but the record high for today is 92F. Can tell we are in early spring now, with record highs in the 90F degree range and record lows on some days still down in the upper 20Fs.

SATURDAY: Dixie Alley Storm system Number 1 will trail into North Central Florida and meander as the boundary (cold front) fizzles. Tiny 15% chance of a shower over North Central/ North Florida. Not quite as warm as Friday as SW winds will have weakened considerably on Saturday, with coastal sea-breezes (light). Continued abnormally warm over South Florida with highs in mid-80s, closer to 80-82F Central with A1A coming in between 75F-79F. All in all though, still above average.

SUNDAY: Boundary still around, morning fog likely. Temperatures about the same as Saturday. Shower chance diminishes North Central and North. Warmer Monday (like Friday).

FIRST CHANCE OF SHOWERS? Overnight Monday into Tuesday morning North Central, shifting toward South Central and Southeast Florida Tuesday afternoon as Dixie Alley Storm System #2 will be moving in, and likely through, most of Florida...it gets sticky toward the Miami Metro Area. But we could see more coastal shower chances at various time going into late week and next weekend with temperatures close to normal rather than above average.