A Strong Storm Near East Central Coast is Possible on Tuesday (Perhaps Unfounded)

Brief  Post For Today:
IN GENERAL: Based upon the 12z GFS/NAM model runs only.

Storm system sweeping SE toward Florida this afternoon will sink south into Central Florida shortly after peak heating hours. The front is forecast to come in alignment with the Beach Line and fall stationary between the hours of 2-8pm.  It is possible that frontal boundary could be accompanied by a thunderstorm or two, which would be strong considering the cold temperatures aloft and steep low level lapse rates. There are indications that some sort of 'significantly interesting event' may transpire very near the Kennedy Space Center within this time frame. Possibly a strong waterspout or tornado.


HOWEVER - Please note: The likelihood of said is highly unlikely as waterspouts are not synoptic scale events but rather a very localized event that can happen on even only a fair day with virtually no snyoptic scale features present (of apparent significance). So just exactly what these values portrayed, and the gradient values mean just exactly, is uncertain on my part.
Addtionally, conditions are not favorable for development of a rotating, supercell thunderstorm..at least not as normally potrayed in text books.


But worth noting in the images are: A strong 100o mb vorticity bulls eye just offshore (very odd!!) with moderately strong vorticity riding up the east coast which intersects the more outstanding bulls-eye feature, ample all day sunshine to increase instability even at the coast since most of the day there will be a land breeze which will swing toward paralleling the coast sometime during the mid afternoon, very high 700mb RH values in a highly confined / tight area, and a very strange forecast vertical sounding...during the time of this sounding surface winds are forecast to be calm on the ground,. 

Some select images from the NAM and one from the GFS are included below: 

SIDE NOTE: In the great beyond, it is looking more like the above average rainfall totals going into next week that were referred to in the past two posts and as forecast by the big wheels who specialize in such matters is heading toward fruition. High instability will be mounting over the Gulf of Mexico waters during upcoming days under neath a strong capping environment of near clear skies. As a result, this heat energy will not be permitted to be released ..being shunted toward "Somewhere" in the SE and Gulf Coast states. 


Should this be the case (it is just now beginning to get underway today), the Gulf  waters will have ample and perhaps accelerated time to warm up (read into that statment as you will).


 A closed 500mb low is forecast to reside well to the north of the state, with ripples of energy passing primarily north of the state, but even still, the forecast situation portrays an enviroment that would be ripe for afternoon thunder from time to time - favoring the east side of the state-, and perhaps an all out rainy day here or there. The most of the rainfall would be just to the north of the state as current depicted by the GFS run of 06z last night going out toward the 20th and beyond:
Forecast rainfall by the extended GFS :

TOMMORROW'S PARAMETERS: These can easily change by the next run. and likely will to favor another location. However, I do not believe it will change significantly in regard to where an amplified boundary of some sort will be located across East Central Florida, favoring the coast and inland along a narrow corridor. It's best not to necessarily focus on the center of these values in some of these portrayed, but rather areas that lie along the sharp edges that define them. (the gradient).

Tornadoes/Hail/ Past 2 Days - 2 More Days To Go With This Sytem

The Cat Eyes NW Iowa Before The Tornado
Event Even Began - The Cat's Sixth Sense
at work

RECAP: Clear and warm in Florida yesterday and more for today. Just a quick recap of the events that have transpired that past two days elsewhere. A few days ago I mentioned that the upcoming event, (which is now the current one) might not have quite as big of a number of storm reports as the record breaking last one, but I'm not so sure now. Already, we have had more tornadoes than the last one; this was expected. But it is not over yet.

We see in the second image that yesterday alone there was 27 (not official yet) tornado reports. Some of those might be duplicates, or some more might be revealed. I've included some radar images below of one of them. There was also 3 tornadoes the day before in Oklahoma . This go around, there are more hail reports than wind ones, with a running total so far of 610 reports total . Still nearly 800 more to tie the last event. I think we will break it by Tuesday morning.  We can see there was two significant areas yesterday responsible for the reports by the image above. Siblings of the same parent storm system.

Lola, my cat, was eyeing the Border crossing from Nebraska into Iowa for storms that initiated in Nebraska to become more surface based as they crossed into Iowa beyond the Missouri River, possibly generating tornadoes as a result...in the image above where all the red dots are ... those are tornado reports. Good eye, Kitty! She even nailed the track of part of one right there with a yellow highlighter to prove her point as shown in the image above.

Here is some radar imagery. The first image was the storm that started the whole. thing. It cross the Missouri River into Iowa and crossed right over Sloan, Iowa as a developing supercell.  from that point on the storm reports began to filter in. Shortly thereafter, it entered a region of lower lifting condensation levels and immediately became fully rooted in the boundary layer and tornado'd...for quite a while in fact!. This tornado was a large, wedge tornado that directly hit the city of Mapleton. There is already You Tube videos out there you can see by doing the search in You Tube's search engine. There are some other very small townships that appear to have been in the path as well, but they are so small we'll probably never hear about it.   The second image is the supercell storm on radar in full birth mode with the hook clearly apparent. We might even be able to see the debris field by the darker red colors curling around the hook's appendage. This was a monster tornado reportedly 1/2 -3/4 mile wide...the video I've seen back this up.

Lastly, this final image is taken from the Des Moines, NWS radar. The arrows I've drawn in  point to SIX storms lined up. all of them rotating. This is a radial velocity image at Tilt 2. It depicts in bound and out bound winds toward and away from the radar's location by the color schemie noted on the right hand column of the image. In bound  directly next to outbound indicates rotation. Makes sense.
=====================================================
FORECAST: Really not much of anything other than what we've seen the past few days until possibly Tuesday. Therefore:


TODAY: Pretty much instant replay today.  High pressure was suppressed a bit to the west of the state last night as the storm system that generated all the storm reports over the East Side of the country and its associated trough moved SE and offshore over night. Therefore, winds will be NW and light, becoming more north with time..but nearly calm at times... expecting a delayed sea breeze this afternoon with inland highs in the upper 80S and a few low 90s; closer to the low-mid 80Fs right at the beach before the sea breeze kicks in.


Another big day for the upper Mid-West and Great Lakes region will commence around 1pm their time and be ongoing well into the night. A squall line will eventually form that will cover vast amounts of landscape going into later tonight and tomorrow which will be on going all day tomorrow. Hence, imagine all the storm reports that will filter in. Today looks like another big day for tornadoes..or at least the potential is certainly there, especially over the North Half of Wisconsin down into NW Illinois perhaps...parts of South Minnesota as well. Others could occur into NW Illinois. The squall line won't materialize yet today.


MONDAY: Possibly warmer than today, especially east side where there may not be a sea breeze. Dry otherwise.  The squall line will be passing through the Deep South and into the Mid-Atlantic Region. More storms reports ad naseum will be flooding the SPC Data banks.


TUESDAY: The remaining last gasp of the frontal system reaches Florida, with the last possible chance of severe gone in general.  I will go into the details regarding this day either tomorrow or on Monday, since the situation that MIGHT occur over a small portion (s) of Florida has been changing with every model run. So far, there's been just enough to keep things 'interesting'.


But for now, it's safe to say that the information coming in has been latching on favoring all of North Florida for rain, with a Southeast Slant toward the East Half of North Central Florida during the course of the afternoon.  For several runs now the front to the north weakens..but appears to send an outflow boundary further south toward North Brevard later in the afternoon as sort of a "Faux Front"..the actual front never really makes it south of St. Augustine.  If this occurs, there might be some sort of Mesoscale Accident somewhere over Southern Volusia County southward into the North Half of Brevard. It would include some lightning I suppose. Hard to tell for sure. But it looks like some folks could get a swat at some small rain fall totals less than 1/4".


The last gasp of the "Faux Front" dies and pulls off shore Brevard after dark. South Florida might also have some thunder, but the chances down there look pretty meager. But who knows, it may be that the area from Boyton Beach to Miami will end up with the thunder for an entirely different reason not associated with the front before Central Florida does right where the front is supposed to dissolve. Temperatures aloft even that far south will be cold enough.  But north of Central Brevard and north of that is where the even colder air and winds aloft will reside. Some of the storms at this point by all appearances could be efficient lightning producers. In either location with the cold 500mb temperatures at play.


NOTE: The Storm Prediction Center has most of the state under a "See Text", meaning weather worth noting could occur on Tuesday. But if I were a betting man I'd whittle it down to NE Florida from St. Augustine north...and the East Side of the State from Southern Volusia County south  to Southern Brevard..mainly east of I-95.  The other area would be the east half of South Florida South of West Palm Beach, especially close to the coast.


BEYOND: Table turning here and there. Two consecutive runs showed the state would be almost dry ...totally blowing away the long range forecast of above average rainfall for most of the state. However, after seeing the 06Z runs, I'm not so sure this will be the case. In other words, more rainfall looks to be back in the picture for more of the month for a wide variety of reasons from time to time. Should be interesting...Time will tell.

Nearly Hot (Inland) Sunday - 'Capping' Warm Layer Aloft To Break Down By Mid-Week

LATEST EXTENDED PRECIPITATION FORECAST VALID: 4/16 -4/22
NO CHANGE FOR FLORIDA SINCE PREVIOUS EXAMPLE WAS POSTED WITH AN INCREASE
UP THE U.S. EAST COAST  (PREVIOUS POST END TIME WAS 2 DAYS EARLIER

TODAY: High pressure prevails over Florida, much like yesterday, although the surface ridge axis may have sunk south a bit today. In turn, chances of a shower far SW Florida look very slim...in fact..that is the case state wide. Land breeze over night along the coasts  will be over come by diurnal afternoon sea-breezes with a collision near the spine of the state near sunset with no affect. Temperatures aloft remain to warm and sufficient moisture is lacking as well. 


Meanwhile, a very significant severe weather situation is setting up for the Central Plains states later today where severe weather/tornadoes/large, damaging hail is a given.  Even as I write I'm seeing the values of various atmospheric parameters needed for the "Severe Weather Cake Batter Recipe" being revealed on an hourly basis. Additionally, severe weather has been ongoing in part of the Ohio River Valley as I write such as in Kentucky and West Virgina.

2PM EDT RADAR WITH TORNADO /SEVERE THUNDERSTORM WARNING OVERLAYS.
A LARGE AREA HAS BEEN UPGRADE FROM A SEVERE THUNDERSTORM
TO TORNADO WATCH BOX, WHICH GENERALLY ENCASES THE ENTIRE REGION
WITHIN WHICH THESE STORMS RESIDE

SEVERE STORMS/TORNADOES/SQUALL Beginning late this afternoon through Early Tuesday to impact a large portion of the country. Believe this storm system will be more significant that the one of last week in regards to tornado potential (and some could be quite strong) as well as a large hail threat; as opposed to mostly a marginal wind threat that impacted the eastern U.S. last week. NOTE: The bigger area of concern it not the area shown above. It will be over portions of Nebraska, Iowa, and South into Oklahoma to NE Texas..spreading east and expanding east , north and south through Sunday.


SUNDAY: Close to nearly HOT inland. Near classic inverted trough up the spine of the state form South to North  as temperatures reach the lower 90Fs over a broad expanse. All coasts are clear though with highs in the mid-80Fs , peaking early in the day.  But note the saving grace; dewpoint temperatures aren't going to be as high as would be the case in the summer, so tomorrow ill be like a 'taste' of summer without the salt. Coasts are 'clear' that is, except from 'Beach Flockers". Yes, "Meet the Flockers" is more than a movie.   This will be like the polar opposite to the "spine of the state" cold spells Florida experiences in the winter when a ridge extends from north to south.


Expect to see the hordes pouring out of the urban inland areas like ants fleeing the mound for sugar neatly posing as a line of sand along the coast. The severe weather will continue tomorrow far from home base as well, as the responsible upper level system moves East toward the Western Great Lakes region and an appendant cold frontal extension of this systems slices south through the Southern Plains into Texas.  All forms of severe weather are possible within these regions tomorrow.


MONDAY: Similar to Sunday, although perhaps not quite as HOT inland due to less than perfect conditions for a maxed out heating event. However, the East Coast will bear more of the brunt because the high pressure ridge axis that will have been stretched East to West across the state  at the mid-levels will start to drop south in response to the large storm system pushing across the Mississippi and Ohio Valleys, with the front pushing through the Deep South as well. 


In turn, not sure we'll get a sea breeze on Monday  north of West Palm Beach which will be closer to the ridge axis with less synoptic scale gradient WSW - SW supporting flow further south.  A late seabreeze is always possible though, just later than normal. Otherwise, dry.


TUESDAY: The dog tail end of the major storm system will pass through Georgia and cross the I-1O of North Florida Tuesday morning, and sink only slowly south toward St. Augustine trough noon time...with possibly additionally inching further south through late afternoon.  The last of the upper level winds with this system will pull out and away by early afternoon. There will be a chance of strong/marginally severe storms north of St. Augustine between 11am -3pm as is being made known by the NWS there and The Weather Channel, although I don't really see it to be a very big deal.


*** INSERT: There is the possibility that, although not reflected in any forecast and only ONE model, that as the system over North  Florida starts to collapse an Outflow boundary will push south into South Central Florida and meet a  region of greater instability further south over South Central Florida.  This would actually be the leading edge of cooler air aloft (and hence, a portion of the Subject Line of this post necessitating explanation). That being, erosion of the mid-level cap of warm air. This will be a very subtle event,, yet will be just the beginning of a new weather regime for the state.


 The GFS Model has shown for three consecutive runs that this sort of boundary which aloft will be simply a fall in heights of the standard 700mb level (and cooler air)...will be enough to establish a zone for thunderstorms or rain showers to form somewhere over South Central Florida after 5pm.  This activity would drift slowly toward the NE but weaken before reaching the coast. Again, this is merely a possibility. But the more significant thing to come out of Tuesday as 'boldly put' above will be the loss of the strong thermal 850mb lid over Central and parts of South Florida that has been in place.


WEDNESDAY: With virtually all upper level support far removed after sunset and the ridge axis now even further south..it looks like the front will slide through the remainder of Central Florida overnight and into far South Florida by daybreak where it will remain.  Temperatures will be back to normal but the atmosphere will be a bit like a lady in waiting at this point with nothing to do  other than to generate some showers and perhaps thunder over South Florida ..favoring the SW side with a prevailing ENE-E wind most of the day.


THURSDAY: It appears the boundary will lift back north on Thursday as the displaced ridge attempts to reassert itself by building back toward the N from the SW...but will get hung up along a  line nearly paralleling the Turnpike up and down the state. This boundary may act to instigate some thunderstorms, some locally strong if this even materializes at all, due to cold air now aloft. Mainly west of I-95 for portions of South Florida and all of Central. There would be a convergence zone set up with the boundary where it meets  the east coast sea breeze. Would be very interesting to have this materialize...could make for quite a show west of I-95 from Volusia South to Okeechobee County, becoming less defined over South Florida where warmer air aloft remains.


FRIDAY: Have already bitten off more than I should chew, but I'm hungry for some thunder.  Next big storm system will already have been approaching the state on Thursday..and in response the boundary lifts north and east to Central Florida before washing out.  Could be another day of thunder favoring the East side of all of Central and South Florida, although The Weather Channel is showing "Sunny" on TV right now. Okay, so maybe that won't be the case.  But here's hoping for some drought relief.


CONCLUDING COMMENTS: Please note the image included in this post and the valid time. I believe they are seeing what I am (most of which I have not written about and is too lengthy an explanation to go into dissertation mode). But it does look like a  good chance of strong/severe storms going into Late Friday or Saturday (n that time frame, more likely Saturday) and a following short-lived respite, the extended out look is showing many days of possible thunderstorms off and on. 


NOTE: The above average precipitation depicted, it must be understood, is because this is normally considered our dry season before the summer thunderstorm season commences. So ABOVE AVERAGE  needs to be interpreted with that in mind. It does not mean insane heavy rains all the time or all day soaks. But who knows, maybe we'll have one or two of those somewhere along the line.

TODAY- COWS in Iowa!!

Past big events
in Oklahoma

A Quick Comparison Of the NAM Forecast DSM 21z Hodograph With Past Big Tornado Events in Oklahoma

Consider other hodographs today as well because although it might appear at first glance that tornadic storms would be most likely only when the

hodograph shows vertical shear that veers strongly with height, such storms are also possible when

Fsct 12z DSM Hodograph

the hodograph is relatively straight. Considerable streamwise voracity may be present with a

straight hodograph if storm motions lie significantly to the right of the hodograph. Such deviant

right motion is commonly observed with severe storms, especially isolated supercells. In straight

hodograph environments, the effect of vertical shear is to shift the storm's precipitation core onto

the downshear side of the storm, where it then tends to suppress and eventually split the updraft

(B E. W. McCaul. Jr.. Steve Lazarus. Fred Carr)

See the Crazy COWS grazing (Cross Over Winds) from 850mb –700 mb  level winds over Western Iowa, NE Nebraska, and SE South Dakota at 21Z? And the extreme high Energy Helicity Index values along the upstream backed winds axis running over and to the east of DSM (Des Moines).

FCST EHI 21z

The North Atlantic Oscillation

NAO: "The North Atlantic Oscillation Impact on Temperatures, Precipitation, Snowfall, and Snow Depth"

Latest guidance from the ECMWF Model, commonly referred to as "The Euro", indicates for several days/runs that we will be entering a period of a moderate to strong positive phase of the NAO. What 'could' that mean? Here's some information. Lsimple click on the Title of this post.

"High" and Dry Through The Weekend With Sunshine Abundant

HIGH PRESSURE AT THE SURFACE AND ALOFT
THIS IMAGE IS SURFACE TEMPERATURE ACTUALS FOR 2PM THIS AFTERNOON

Weather for today through Monday at least will be dictated by high pressure at the surface and aloft over the state of Florida. With light land breezes at night and sea breezes during the late morning through late late night, but like in the summer. Afternoon highs will vary from the low 80Fs along the coast to the mid-upper 80Fs inland. Temperatures all locales will warm a bit more on by Sunday.  A shower of two could develop on an day from far SW Florida to Naples, perhaps far NE Florida as well but the number of showers and strengthen is not worth mention.

FOR EXAMPLE: HERE IS THE AVERAGED WINDS ALOFT. NOTE THE LOCATION FO THE HIGHT AND SOME MOISTURES OVER SW FLORIDA AND NORTH FLORIDA

NOT MUCH ELSE TO MENTION WORTH MONDAY: During the weekend and into the early part of next weak a very strong, well devised system will move across the county juch like the once of the other day. However, this system is not directly thought to affect the state other than near I-10 on Monday


TUESDAY AND BEYOND: As noted, there is strong high pressure over the state. Strong systems approaching from the west will eventually suppress this high south and east with time..but just exactly when is too soon say say. The only consistency between models is that one of the systems will eventually erode the trough enough to allow strong winds aloft and more moisture  in as well. The first sign of this chance will be Monday.


RAIN WHEN? Rain chances pick up a bit more around 4/15, with a few meager chances haere and there but not worth mention

Florida Might Be Able To Break The Drought by Month's End !

An Example of Possible Precipitation Totals Over a 4 Day Period Ending Next Friday Night (April 15th)

TODAY THROUGH MONDAY: Florida will be under affect of a high pressure ridge at times centered directly over the state today through Monday. During this time some strong/severe weather producing storm systems will ride up and over the high pressure north of Florida, which will feed  moisture and heat into much of the Eastern United States as far north as Minnesota.  The weather will be dictated over the state by warmer afternoons working into the weekend (actually before that time in some locations) which will expand in coverage into much of the Eastern States as far north as Minnesota. Very cool morning low temperatures will be a thing of the past for all but NW Florida (at times). 

This COULD be significant further in time as this latent heat will eventually accumulate as energy to be transported...somewhere.  As we can see in the image above that energy could translate as storms and rain with time as upper level parameters become more favorable for its release (colder air aloft). First will likely be a squall line to develop into the weekend and/or two separate regions of severe weather north of the state.  This image is one example of what could be the net affect for the period of April 11-15 over the Southeast United States as these systems erode the ridge, finally affecting the state. 

Per this same model, this is only but half the story!

Temperatures will be coolest near the coasts with highs 80F- low 80Fs where inland and SW Florida as well as portions of the state's spine could break the big  9-0 but mostly mid-upper 80Fs will be the rule.  Although sea-breeze collisions will occur on several afternoons, warm air aloft will preclude the formation of nothing more than clouds and perhaps a sprinkle or shower toward the favored west side of the state south of Tampa during this time frame with the east coast sea breeze being the most dominant, at least going into Monday.


TUESDAY: The first of possibly 2..and dare say..maybe 3 storm systems will cross the Western tier of states, gradually working to erode the ridge's influence. It will be a long, drawn out affair...but with time the warm air aloft in the mid-upper levels will be eroded from north to south over the next week, but here on the ground our temperatures will remain warm.  The first of these systems will make a gradual sink into the Panhandle area on Monday...by Tuesday there could be showers and thunderstorms over North Central Florida, working south with time into South Florida through Wednesday. If this does even occur, severe weather is not anticipated.


BEYOND: All things hinge on the long range forecast in regard to the image shown above. At this point in time perhaps it's wishful drought breaking thinking...in fact, it is. But at least there it is in print. After writing that sentence, I thought to myself, "hey , I wonder what the folks at HPC are thinking? I could get their image for comparisons sake, whether or not it is in agreement"

NOTE THE EXTENDED FORECAST ISSUED BY THE HYDROLOGICAL PREDICTION CENTER FOR APRIL 14-20, 2011:

The extended calls for Above average precipitation April 14-20th right during the normally driest time of the spring drought season...bizarre!

IN ESSENCE: To go out on the first limb of many (which I will not do)..the first limb will be one which could be a severe weather event beginning sometime around the 14th-15th time frame as noted yesterday (another possible event jumps out in guidance in an even later period). The ECMWF and GFS last night varied SIGNIFICANTLY with the handling of this time frame...but they seem to be falling in line in regard to the eventual outcome going into Tuesday through the 15th, and clearly from the image above the folks at HPC are willing to lay some bets on this.  ALL of Florida has a 'chance' to wipe the slate nearly clean of drought, or at least put a good dent in it, by the end of April if the GFS run of 8AM this morning comes anywhere close to fruition, considering that if it is correct (which it almost never is that far out in time)...the rains would continue until about the 23rd.  Please note, this is a Big "If".

Very Pleasant North/Central, Clouds South Today - Unsettled Later Next Week

Squall Line Lightning Over the Banana River south of Kelly Park

RECAP: Squall line cleared all of Central Florida by early afternoon, continuing through South Florida and the Keys by 4pm.  This organized line of storms originated from near the Ohio River Valley region 36-48 hours earlier...and has left it's dying energy, mostly moisture over far South Florida and the keys. A waterspout was sited about 7 miles offshore the Cape, and another was seen about 1 mile east of Patrick Air Force Base as well. There was some severe category level storm reports from wind in Florida, but not of the intensity or coverage as those observed last week. This was expected to be the case, since winds aloft were not as strong and temperatures up there were not as cold either. 

Here is the radar image as the system crossed along "The Great Dividing Line". It was at this time the squall encountered the richest dew point temperatures of 70F and above and the more unstable air over the South half of the state which had developed after sunrise. Also note the rotating single celled storms CLEARLY outlining the Gulf Stream. Kind of neat! Multiple waterspouts were supposedly reported from those offshore storms. I'm not surprised at all. It would have been fun to paddle out there with a long board equipped with a GoPro Video Camera to go "Storm Chasing, Doggie Paddle Style

AND HERE ARE THOSE DEW-POINTS. NOTE THE  NORTHWARD"NOTCH"  OVER NORTH BREVARD. THIS IMAGE WAS ACQUIRED 45 MINUTES PRIOR TO THE ARRIVAL OF THE SQUALL LINE AS SHOWN IN THE ABOVE IMAGE.

There was some weak subsidence in the air mass immediately preceding the line which precluding the southbound system from efficiently "inhaling" the juicy air mass immediately ahead of it over Central and South Florida. This, in fact, seemed to be a factor with this line during it's entire journey from the mid Country. My personal observation of this fact could confirm that, at least over Central Florida. As the system approached, the atmosphere acquired a 'hazy. muffled' appearance  10-20 miles in advance of the squall within the sinking air. 


Additionally, the sound of thunder seemed to be 'ducted'...only close to the ground. Thunder did not roll and roll..did you notice that if you are a reader and were in an area that had lightning? I did not see any cloud to cloud or in-cloud lightning. Only cloud to ground...and most of the lightning preceded the rain or occurred as the rain began. Might have been just where I was at though.


 An enhanced section of the line popped just a mile or so to the north over the Air Force station at the Cape, passing just east and north of Port Canaveral. That can be seen if you look closely at the above radar image. This occurred as the line met the higher dewpoints, cross sectioned with the higher low level helicities off shore.


NOT SURPRISED: Low level helicities were being analyzed and forecast for the coast and just offshore for 24 hours prior to the line's approach.

THIS IS THE NAM FORECAST FOR 11AM..1 HOUR SLOWER THAN WHAT OCCURRED.. However, this shown was a 33 HOUR forecast. NOT BAD!! We can see the gradients of Cape being pointed out over South Florida by the black arrow's text. Whereas this image (red arrow) portrays the low level helicities in the bright colors. NOTE the area off shore and over the Gulf Stream in faded orange...which eventually MET the south bound values east of Brevard County. They met and POOF...waterspouts and lightning, which the Port area had the benefit of experiencing as can be seen by the image at the top of this post.

TODAY: Front has cleared all but extreme South Florida..mainly the Keys. Ample low level and some mid level moisture remains, enough to generate clouds which thin and lessen the further north one gets where the air is drier at those levels. Just enough over Central to generate some flat topped stratocumulus clouds.  Could be a rain shower by the time the day is through over far SW Florida near the coast.  High pressure is located just East and North of the area this afternoon. This will sink south through the weekend, and as such clockwise flow around it will become SE overnight tonight which will advect higher dew point temperature air into all of Central Florida over night and through tomorrow. Over night lows will be a good 8 degrees warmer tonight than last night over Central and even warmer than that along the coast. Clear skies overnight Central and North.


TOMORROW: A warmer start to the day...and a warmer day overall everywhere in the afternoon. Winds along the East Coast will be SE-SSE at times and breezy at 12-18mph during the late afternoon especially as mid -upper 60F degree dewpoint air rides up the East Coast along and east of the Gulf Stream toward Sun Glow Fishing Pier. This will be the theme of tomorrow, with partly cloudy skies...of more puffy cumulus nature. 


There is a very small chance of some showers or even a thunderstorm from near Lake Okeechobee to just west of Orlando along Route 27 (Clermont/Bok Tower area) and/or over toward Central Osceola County and into Central Brevard very late afternoon to late evening due to a sea breeze collision.  The chance is close to zero; however, one model suggests this to occur 'somewhere' within ONE of those areas (not all of them), whereas another model shows zip.  That same model has shown it to occur on 4 consecutive runs, whereas the other consecutively shows nothing. The reason for this lies in the forecast of the mid-level temperatures. One of them is too warm aloft and 'caps' the atmosphere for upward moisture transport, and shows increased convective inhibition, which totally jives. However, the other is quite generous in comparison with a thunderstorm somewhere with air aloft just a few degrees cooler. My bet is it will rain somewhere with the upper trough in place and upward warming slow to occur as opposed to that at the surface, but this will be reassessed in future models with plenty of time for an official forecast made public should conditions warrant. Probably way before the next blog post of tomorrow morning we will see or hear a rain chance from the National Weather Service or on the news...but so far all is mute regarding a rain chance..


SATURDAY-MONDAY: Continued muggy and warmer with highs in the mid-upper 80Fs, and some low 90Fs far SW Florida. Winds SSE initially becoming S-SSW late Monday or Monday night. During this time frame warm air aloft over runs the peninsula as continuing warmth of the peninsula rises without impedance to the mid levels...this would be due to the fact we will have another system approaching from the west later next week..and the flow ahead of it will 'buckle'..or rather..Ridge/. So ,do not foresee a chance of showers. But plenty of moderate cumulus away from the east coast during the afternoons (inland) and most of all South Florida, with post sea breeze subsidence behind the east coast sea breeze each afternoon to further squelch the chance significant cloud coverage east of I-95 north of Ft. Pierce.


MONDAY NIGHT/TUESDAY: A storm system highly worth noting  for a small area of the Central/South Central Plains will be that area beginning tonight and into tomorrow and beyond will move east across the Mississippi River Valley Basin and toward the Mid-Atlantic by late Monday. The high pressure will sink south even more and allow winds to become more SSW. The associated cold front as it is so portrayed both all models will move into Central Florida on Tuesday around noon time or shortly thereafter. This front could be accompanied by some thunderstorms or showers, mostly along ...you got it.."The Great Dividing Line of Central Florida" which runs from Tampa to the Port. Other showers and storms could occur futher north, but due to the timing of this boundary passing through North Florida overnight and early morning instablity for thunder will be somewhat, but not entirely limited. The front could stall and pull out to the east during Tuesday. Leaving the South Half of East Central and South Florida in a rain chance through Wednesday.


 Chance of showers and thunderstorms on Tuesday as noted above, decaying shortly after nightfall as the boundary moves into South Florida or goes stationary very close to the location the boundary of today now lies over South Florida where rain shower chances will continue the following day.


***NOTE: Timing of this front will likely change as the time approaches. Therefore, the above stated is purely theoretical at this time. The front might never even reach South Florida at all.


GOING INTO LATE WEEK/THURSDAY: It's becoming close to the point that we can safely say that a very unsettled weather pattern over all of the state at various times will be the wild card in regard to rain and storms.So far, especially the South Half of the state, but initially all of NW Florida and the Panhandle. Another major storm system is going to affect much of the country working into next week. Wide spread severe weather is anticipated from the Gulf to the Great Lakes and parts of the NE States...and I expect there will be a higher number of tornado reports with this system than with the squall line of the past 2 days. Most of the exact same areas will be impacted by this system as well, including Florida.


However, the nature of this system, as it now appears, will manifest itself in an entirely different manner...at least for a portion of the time, as it crosses the states North of Florida. It probably will not be preceded by a shallow layer of subsidence and a squall line...at least not for the early to mid-time portions of its 'existence'.


The impacts on the state of Florida, and the timing of when exactly these will be sketched in stone remains a bit fuzzy as of the latest model runs, but all models are agreeing that a big change is in store sometime around April 14th for at least a three day period.  There is an indications that a large upper level 500mb low pressure area  (rather than a swiftly moving east bound trough) will cut off over or just west of Florida  resulting in very cold air aloft, yet warm air at the surface until there is a frontal passage. This could end up just being a cloudy/ rainy series of day (s) or very stormy ones. There does appear to be a least one window of opportunity for severe weather over Florida as much as a full day before the actual system moves in (or around April 14th).  


It is not shown yet, but what I will be watching is the area over the Loop Current. Should a surface low form here...things get very interesting. But as of now, there is hardly but one minute hint of something 'fishy in the waters of the loop current other than tarpon and Sailor's Choice".


Low and mid-level wind fields with this system as it appears now will be very weak...so it does not look like a tornado threat will be in the making at this time; however, there is still much to be determined at this point in time. The configuration this far out in time concerning this "POTENTIAL" system leaves a lot to be desired in regard to the low level features this far out in time. Something doesn't look quite right. Perhaps a secondary surface low will from in the Deep South near Florida..,seems possible. That would change everything.


For instance. at no time during its 3-5 day visit is a cold front portrayed to pass through the state by the time all is said and done once the upper low lifts out. In fact, we do not know how long it could linger, or if it even will. If it does not cut off, as only the latest GFS model portrays this morning, the impacts will be more significant, but the chances of rain fall and/or storms will be of short during. Could be a two day event...or a 5 day event.  


" Round and Round and Round "she" goes, where "she' stops...Nobody Knows"...Knowbody.

Tornado Watch In Effect North Florida -Severe Thunderstorm Watch Likely Central

Anticipate a severe storm watch will be issued as shown. This image was created at 4am

COLD FRONT will move into Central Florida and begin to become more aligned from ENE-WSW and almost E-W with time this afternoon. The front will be location from near Titusville to South Tampa Bay and make little if any further southward motion this afternoon until after 4pm.


During this time...some forecast values show respectable Bulk Shear, CAPE in the 1000-1400J/KG range, and Lifted Indexes of -4 to -8C accompanied by somewhat unusually cold temperature aloft. In other words, the atmosphere will be moderately unstable all through the early afternoon over Central Florida. Also this area will be in an area of upper level diffluent flow at the jet stream level coincident with the sub tropical jet over South Florida and the mean continental polar jet exiting Northeast Florida, placing Central in the Left Exit region of the departing continental jet stream streak of higher winds aloft
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All of these factors combined will promote vertical upward reaching storm tops during the first portion of the day. Expect a lot of lightning, strong wind gusts over 58mph, and possibly some small, non-severe sized hail in the strongest of storms. Secure ALL loose objects now such as lawn or pool furniture, and get chores down early, to avoid the rains.  Some localized urban nuisance flooding could also occur in those areas you know are prone to doing so.

Forecasts, and actual observations since this image was saved, are showing pockets of low level shear and winds forming along and axis running from Tampa bay to Port Canaveral. Much more now that what this image shows..'THE GREAT AND MAGIC DIVIDING LINE!" Of North Central and South Central Florida

Bulk shear from the surface to about 10,000 Ft  we can see is laid out along and north of the line from Tampa to Port Canaveral. This is not expected to change in location this afternoon...only weaken with time.

The Energy Helicity Index at 1pm from the Ground to 3000 KM will be maximized this afternoon along the East Coast of Brevard through Martin Counties  where storm relative inflow at 2000 ft is forecast to remain from the ESE-SE. We see the front at 2pm only as far south as Daytona Beach

 In short, we can expect a rain day across all of Central Florida once the rain at any one location begins,. Heaviest rainfall could be near Tampa and near Central Brevard  south to Indian River County. 


Strongest storms will occur along the leading edge of the first storms, however additional lightning storms could become strong to marginally severe through the early afternoon hours until the strong upper levels wind lift east and north...and away from Central Florida


Once these winds pull out, the front will be permitted to drop south through South Florida during the late night hours. It appears the winds will have entirely exited the East Coast right over the Cocoa Beach area late in the afternoon...these may be accompanied by one last gasp heavy rain shower.


Rains will end from West to East...last leaving the East coast near or shortly after sunset all areas.


A Week of Very Pleasant Weather will follow, so hold tight. After today we're gold for quite some time...with a warming trend working into the week end. It will truly feel like Spring by early next week. FLORIDA spring that is.

Thunderstorms (Some Strong to Severe) Tuesday Beginning Early

Above is the latest official forecast issued by the Storm Prediction Center today for Tuesday issued this morning with a questionable area in the black box. However, continue below regarding this discrepancy. Note that the above is valid thru 8am Tuesday morning.

TODAY: Very pleasant and breezy along the East Coast, particularly of Indian River, Brevard, and Volusia Counties mid-late afternoon. Winds SSE 12-20mph with gusts to near 25mph later this afternoon up the intracoastal waterway. Otherwise, partly cloudy skies with humidity levels on the rise today, particularly near the east coast. Chance of a mid-late afternoon showers in the vicinity of Gainesville into Ocala, possibly west Flagler County into the early evening.

TONIGHT: Strong surface boundary of various atmospheric temperature and wind gradients within a deep full latitudinal 500mb trough is sweeping across the Mississippi River Valley/Ohio River Valley Basins this afternoon, and into through the Deep South. Several tornado and severe thunderstorm watch boxes encompass this region as of noon. Mainly tornado watches as we can see below:

Tornado Watches in Affect. Nearly 400 severe weather related reports have already been logged since early  evening of Sunday night with this storm system as it progresses east. Mainly from high wind and large hail

OVERNIGHT: Here is a time of contention is POSSIBLE (not definitie) for North Central and a portion of South Central Florida.  Note that at the time I started this post, , Florida was not within a threat for severe weather, per the graphic at the top in the 8AM time frame.

However, by all appearances, there was that area in the black box that really drew my interest. In this area I checked forecast soundings from two different models for the time period along with a VAST plethora of other atmospheric parameters and come to the conclusion that the region in the box, or roughly Flager, Volusia, and the North Half of Brevard County as well as parts of Orange and Seminole Counties stand a shot of severe weather during the hours of 6-8AM. Kind of odd considering the actual surface boundary of contention (the cold front), will still be way back in the panhandle.

Based on sounding data and all the other goodies used to make this determination, it appears a squall line composed of high bulk shear and cold air aloft along with moderately strong very low level wind speeds, partly from a suddenly developing low level nocturnal jet streak will blossom during a 'transition time'.

What is the 'transition time'?  Guidance has indicated for 3 runs that the full latitudinal 500mb trough will begin to acquire a 'negative tilt' where the base of the trough will swing forward ahead at its apex and be aligned a bit from NNW-SSE ...in other words the base will proceed the axis of averaged flows in lower levels of the atmosphere. 

During this time a subtropical jet across the Southern Gulf of Mexico will be working northward from over South Florida...the two are SUPPOSEDLY going to phase together right as a 500mb vorticity maximum swoops through the base of the continental trough...strongly across Central Florida. If this occurs, expect rapid storm develop between the hours of 3-4:30AM which will move almost generally E-ESE and strengthen with time while approaching the coast an hour or two before dawn through sunrise to just after sunrise.

There actually is a few locations that it could be especially nasty...for instance..over North Brevard surface instability will be greater prior to this event than that further north, with dew points approaching 70F degrees right long the Brevard County coast to the Port. As I write, the SSE winds of today are advecting this juicy air up the coast and into this region.  This low level instability does not appear will reach north of Brevard County. However, further north into Volusia and Flagler Counties...winds aloft are a bit more strongly stacked ...with higher bulk shear throughout the 'bulk' of the atmosphere. 

Therefore, I drew in the box as noted at the top of this post...even though this area was not outlooked for active weather during this time frame by official outlets. It looks like, should this occur, the activity will have cleared the area by 9AM, if not sooner. Straight line winds of 60mph and hail of 1-1.5" inches are possible (although stronger winds are possible).  Forecast soundings also show a bit of a "dry slot" just above the ground...which will be conducive for the cold, denser air aloft to descend and accelerate through the drier air as it reaches the ground. 

Vertical velocities (upward motions) through the low and mid levels during this time frame are conducive for the formation of hail as well...the number (hail size) is  just a gander, based on the fact that  the lifting condensation levels will be very low during this time frame. In other words, condensation of moisture into rising air parcels will begin close to the ground at the same time the anticipated low level nocturnal jet will be in play.

It is also interesting in that this is all supposed to occur in an area of relatively high convective inhibition. (an atmosphere NOT conducive for storms)..thus...THIS EVENT IS ONLY POSSIBLE...NOT a Given.

While typing this post, a new Day2 Severe Weather Outlook has been issued...with a starting valid time of 8AM...as we see below:

NOTE THAT THIS VALID TIME FRAME STARTS AT THE SAME TIME THE OTHER ONE ENDED, YET MOST OF FLORIDA IS IN A RISK AREA NOT SHOWN IN THE PREVIOUS OUTLOOK FOR THE SAME TIME (12z). WHAT'S WITH THAT?!

In conclusion, perhaps all that is written above wasn't so far off base after all. The above graphic is valid through all of Tuesday.

OUTSIDE OF THE POSSIBLE EARLY MORNING EVENT: The NAM and GFS models are almost in perfect harmony with timing of the frontal passage proper. They both agree the front will cross Florida 3 hours LATER than previously proposed in all of the model runs the past two days up until just before this post, with the front barely clearing Brevard County at dusk as virtually every wind field, instability, and related parameter ia swept offshore. The front lingers over South Brevard before simply dropping through the remainder of the state with little fanfare.

However, there may be another round of thunder storms with the frontal boundary itself as far south as South Brevard. The front is forecast to cross through Volusia around 2-3pm and slide into South Brevard around 4-5pm before losing much of its dynamic energy. Then, in the process of the sunset and the energy having departed...quickly clears the remaining southern portion of the state in the following 3-5 hours.

BE ADVISED THOUGH: This is only one possible scenario, and it could quickly change with the next run of models. The later frontal passage does not surprise me in the least though.

SOUTH FLORIDA: Totally different bag of tricks. The same vorticity pattern that is set to ignite the prefrontal squall line further north will cross into South Florida in the following hours after sunrise where thermal instability will already be well in place. Wind profiles aloft south of Brevard County quickly become weaker but the air aloft remains cold, so strong winds of 55mph or greater are possible, as is small hail, but timing of such is difficult to narrow down beyond writing that it will be sometime after 10AM, possible much sooner.

Rains/Storms will end all areas, the far east coast last, by 8pm for the most part...and in most areas much sooner than that.

IN SUMMARY: Mostly cloudy tomorrow except over South Florida through mid morning, with a near 100% chance of rain. Showers and thunderstorms, some of which could be pretty strong, or even severe.

TORNADOES: At this time, they do not look likely, but one could occur, as it often the case in Florida with strong or severe thunderstorms. Lips are sealed on where I think those have a 2% better chance of occurring than other places...so as not to raise either a red flag of warning, nor to put folks at ease in thinking the are out of the woods in this regard. Simply know way of knowing.  Even South Florida without the wind fields, could experience somewhat of a mesoscale accident along storm outflows, especially once the anticipated squally area further north could potentially send an OFB (outflow boundary) into the region.

BEYOND TUESDAY: Very pleasant through the remainder of the week. Behind the cold front it is very nice to know there really isn't much cold air! Return to normal or slightly below normal temperatures for a day or two...and that's it. Dry.

Two more potential systems loom on the horizon going into the next 12 days.