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

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

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

Tuesday, April 30, 2013

Showers and Thunder Possible Again , Some Strong Most Likely South Florida

Post today has a big caveat namely for Central Florida. See verbiage in 'red'.
TODAY: Ample moisture is already in place today Central and South Florida. The issue with Central in regard to storms today is an outflow boundary seen on satellite animation which if 'post boundary conditions' hold to form, might stabilize the atmosphere too much for much activity to get going across Central Florida today. Not so much the case for South Florida though, at least not yet. The NAM shows very little activity today whereas the RAP and GFS are consistently indicating some rain. Suspect this might be convective feedback though. It appears the NAM might not have initialized well though on the other hand, which would make sense if the former is true.

Again though, the outflow boundary is a big question mark. On the other hand, looks like there will be good clearing for most areas prior to noon time allowing for quick heating with little chance of storms out over the Gulf stream causing high clouds to stream overhead as was the case yesterday. 

All things aside, with the worst rain-case scenario:

Chances of locally heavy rainfall and some minor street flooding, mainly inland and especially over areas that received a good dose yesterday (where over 2" was not all that uncommon). A few severe warnings were issued yesterday but actual severe was brief and rare. Temperatures aloft today though are equally as cold and wind shear per the SPC Mesoanalysis page is actually greater today, although looking around outside from East Central at this time it looks like a dreary day is in the making and that is about that. But, as can be seen in the image above, not all folks are cloudy.  Again, the bigger downplayer for a rain maker might be the outflow boundary seen in satellite animation. Will the lower levels recover in time? Chances are, it's still pretty early in the day, so it should be able to. Activity might get going just a bit later than previously expected but either way would expect that by 2-3pm showers and some thunder could get popping over at least the west 1/2 of the state and South Florida, earlier South Florida.

WEDNESDAY: Wednesday might be more cloudy than rain due to an expected MCS (Mesoscale Convective System) that might prop itself upstream well out in the Gulf sending high clouds this way. If not, that changes everything. We'll have to see on that one.

THURSDAY-SUNDAY: Chex Mixed Bag  to be determined. The GFS and to a smaller degree NAM suggestion strong onshore flow from a developing occluded system to the NW with a trough extending out and down across Florida. Pressure gradient winds of 20-G32mph, and rain rain rain from Brevard 'mainly' and south for Friday into Saturday primarily  but be advised,  guidance varies from model to model and from  run to run considerably. All guidance is indicating the Omega Block to set up, but the position of the low pressure system on the east side will  the prime determinant. It's simply too soon to know almost until it happens.

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Monday, April 29, 2013

"Could Get "Wild" in Select Locations Late Today, Rain in Forecast through the Week

Tricky forecast (no doubt) for today due to vast model discrepancies  This Cast is based on persistence and newly evolving short term guidance (in some cases)
TODAY: As mentioned yesterday, chance of strong to severe weather in random isolated fashion is possible later today remains with the greatest chances being over Central to North Central Florida with a slightly lower chance for the strongest activity over South Florida.  Given latest guidance trends and visible satellite imagery, the usual South Florida might get started earliest at a less than  'the most favorable time of day' for strongest activity, not to say there could not be some strong storms mostly west of I-95 toward the swamps.

Further north, at this time will be watching for an increasing S-SSE wind up the intercoastal to begin after 3-4pm time frame as the current very unfavorable conditions or rain in Central begin to shrink in size as moisture works into the area. At this time Central is not looking good for hardly a rain shower today, but that could quickly change after 4pm. Outside of model guidance, a more localized late day tilted sea breeze enhanced by gradient flow enhancing low level helicity and shear mainly near US1 toward I-95 combine with the land curvature of the Cape seems to be the best area for strongest activity ..with secondary areas further south and north. Thus, the area to watch late would be Osceola/Orange/ far eastern Lake County  most of Volusia County,  Southern  Flagler County (if high clouds do not affect that area) and North Brevard to South Central Brevard mainly west of US1. However, should a storm anywhere from Central Brevard north through Volusia effectively penetrate the sea breeze and violate 'model rules' a waterspout couldn't be entirely discounted near the water ways or off in the Atlantic.  The bigger threat as usual will be cloud to ground lightning strikes, some potentially far removed from the rain areas, small pea to dime hail, and wind gusts topping 60mph. Again, this would be after 4pm and closer toward the 6-7pm time frame; thus, a preliminary 'heads up and just in case'.

TUESDAY-WEDNESDAY: Not much has changed in the longer range for Florida, as noted yesterday, much is still 'up in the air' regarding what is to occur over the Central Plains toward the Mid West States regarding a mid-upper level low. To add fuel to the complexity of this 'more extended' time frame, guidance keeps going in and out with a mid level low (per previous ECMWF runs and at times the NAM) to form west of Florida as a function from the Northern Caribbean to cross FLorida and/or almost form over the state). On the other hand, the GFS has consistently not shown any such entity. If the latest ECMWF verifies, the rainiest time frame could be Thursday into Friday as a result of said anomaly  Another such anomaly is that the GFS is showing a bit of a mid-level 'warm front' wind shift type line across Central Florida on Wednesday (perhaps instead of that just stated) which could be a focal point for rain and thunder which could make almost anytime Tuesday into Wednesday the big rain day, especially along the east coast. Point is, every day is different than the previous as well as the day after as it stands now all of this week. 

Otherwise, temperatures will remain comfortable with plenty of clouds in the picture. Rain could occur on Tuesday just about any time through Thursday just to highlight that we could increasingly fall away from the after-evening type regime Florida is accustomed to. When all is said and done by the weekend some areas 'could' receive several inches of rain due to very slow storm motions, especially after today.

BEYOND: The prospects for much cooler air has also faded from the picture, come back, then disappeared again heading toward Sunday. Chances are, if it doesn't get here by Sunday, it never will.


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Sunday, April 28, 2013

Strong to Near Severe Storms (?) Monday, Active thru Wednesday/Unsettled Through Saturday

TODAY: Clouds with Sprinkles East Central toward the NW,
thunder possible west coast late
TODAY: Onshore flow continues becoming more ESE-SE-S into Monday. Although cloud cover exists mainly over Brevard County and inland a way, most of the state as can be seen from this above image remains quite pleasant. This was much the case as well on Saturday. Other than some sprinkles, not much going on today with a good breeze along the east coast which might sustain itself going into the over night for a time toward dark and onward along the Barriers.  Chance of thunder focus toward Tampa Bay late today and early this evening, with another shot possible up toward I-10 east of Tallahassee.

MONDAY: Flow becomes more southerly as Southern Branch jet right entrance region nose points toward Florida. Temperatures aloft quite unusually cold, although winds not strong aloft. Instability and lighter surface winds allowing for low level convergence and ample reactive outflow Lake and sea coupled with outflow from early day activity north Florida as well as over South Florida boundaries could result in some strong to near severe thunderstorms namely from marginally strong winds and/or hail, most likely in from the coasts toward Orange/Seminole, Western Volusia, and maybe interior north Osceola County. Activity could be strong as well, but if outflows come into play, it might end up being Central toward to after dark that gets the strongest storms. Activity could run late and into the post sunset hours and migrate off the east coast mainly from South Brevard  and north.

MONDAY image from the GFS. The NAM model is showing a more imposing proposition for
Monday over Northern Orange and western Volusia working toward most of Volusia and the north 1/2 of Brevard though. The GFS is more generalized, but thunder and/or rainshower chances are a pretty good bet most anywhere on Monday through late evening as they drift off the east coast.

TUESDAY-WEDNESDAY: Guidance currently indicates a 'bubble low' could form over South Central on Monday into Tuesday and move off the east coast by Tuesday night. Before then, another shot at strong thunder on Tuesday contingent on cloud cover. Activity could get started before noon time, with the best shot on Wednesday for any stronger activity appearing to be over parts of South Florida while rain showers and some thunder could still occur many other locations. Could also otherwise be cloudy. That is dependant on if that low does form placing North and Central in a more northerly wind flow, albeit temporary for about 24 hours.

THURSDAY-SATURDAY: Upper level low will be cutting off for a time somewhere around the Mississippi or Ohio River Valleys region resulting in more rains in those locations. Expect we might be hearing about river flooding downstream. The impact to Florida remains a bit uncertain, but it seems that at least the chance for stronger storms might have waned by then with cloud cover and or some rain showers in the calling, but exactly when, where, why, and how is still up for grabs as models , even since that last post a few days ago, remain in disagreement on where any cut off mid-upper low might form and how long it will last. One or two model runs even show no cut off at all, thus the forecast for really ALL OF NEXT WEEK is highly variable and quite open to reconstruction at any point in time. Just a heads up when or if watching weather on TV. At this point, the last chance for rain appears to be along the east coast south of I-4 later on Saturday.

BEYOND: If the low does close off, another impulse could approach the state in the good westerly flow aloft around Tuesday or Wednesday of the following week. Much remains highly (expressively so) uncertain.
The threat of much colder air temperatures on the ground though seems to have diminished from the previous GFS runs as suspected might end up being the case, although we could still see a good spread of 50Fs around Sunday morning.  Again, the latest GFS continues to show the cut off forming, with another impulse to form somewhere toward South Texas and head toward Florida the following 48-72 hours...which means nearly 9-10 days from today. How likely?...hard to say.

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Friday, April 26, 2013

Potential For Turbulently Wet to Eventually Quite Cool Beginning Monday or Tuesday

Areas Mainly East and South of the Orange Outlines Could Experience Very wet
conditions from a combination of Arctic like conditions mixing with some sub-tropical anomalies next week meaning very wet, cloudy, and eventually very cool conditions. Much is still TBD.
TODAY- SUNDAY: Pleasant weather for the most part prevails although there might be some increasing cloudiness for parts of Central and South Florida on Saturday into Sunday which would mean a bit cooler where clouds (if they manifest with a quick sprinkle) persist. Otherwise, not much to speak for as spring like weather prevails allowing the trees to manifest foliage and nature in general to blossom forth.

MONDAY-TUESDAY: The above image is the surface depiction for today with the highlight really being in the far NW corner. This is a surface reflection of what is to come well aloft at the jet stream level. Guidance is showing a deep upper level trough to drop into the country's midsection next week while in the meantime a southern branch sub-tropical jet will also be in place from west to east south of Florida. These two branches are expected as it now appears to meet up somewhere over the Deep South toward Florida. Cold air aloft, ample moisture, and unstable air would allow this pattern to become most evident going into Tuesday and more so on Wednesday.

WEDNESDAY- FRIDAY: Both the GFS and ECMWF (Euro) are showing unstable , wet, possibly stormy especially Tuesday - Wednesday time frame but continuing possibly through Thursday or early Friday. Exactly how the eventual outcome manifests will determine what kind of weather will occur heading toward late Wednesday (as it appear now). Guidance varies anywhere from a bit of a subtropical entity emerging from the Gulf and across Florida toward one of not subtropical origin forming over Georgia. If the former occurs weather could get quite windy along the east coast for a day or two with rain mixed in, preceded by a day or two of strong storms in the forecast. Either way, strong storms might end up being in the forecast from cold air aloft and some bulk shear in the upper levels Tuesday and/or Wednesday, or even Thursday.  In any case, under both circumstances, rain chances appear could occur almost any time after Tuesday or at least begin prior to noon time through late evening each day. Storm motions would be rather slow, so (or if so)..rainfall totals in small areas could end up being higher than model guidance is hinting at. On the other hand, what is showing as rainfall might actually end up being solely cloud cover.

BEYOND: Without going into greater detail (on the above), since much surmising leads to only more surprising, the GFS is hinting at unusually cool weather returning come next weekend with lows well into the 50Fs...accompanied by breezy conditions. Again though, the GFS has a tendency to go a little too far with low temperature forecasts in the long range for Florida at least, so will leave that up for grabs until a more reasonable time frame draws nigh.  The GFS has shifted gears nearly every 6 hours beyond 72-96 hours as it stands now (not unusual  but did eerily come into close agreement 12 hours ago with the latest Euro Model, which showed a surface low just off N. Brevard County come Thursday time frame after two days of decent rainfall chances.)Time will tell is about all that can be said at this point, at least for planning purposes.

Necessary Footnote  there has been hints of if not one but perhaps two blocking patterns setting up over the Northern Hemisphere in a run of the ECMWF model, and blocking patterns should one set up and just exactly where (being the next matter to consider) tend to be quite difficult from a future-cast perspective for forecast accuracy as we then are at the mercy of determining just exactly when any said block (or blocks) will actually break down. That is yet another factor to consider in an already what appears at this point to be a complicated, but yet to develop, situation.

This "Example" shows TWO Omega Blocks over the North Hemisphere with the United States at the ver y bottom of the image. The GFS hints at an Omega Block right over the United States in a few runs. Point being, wherever the block sets up, if one does, will be a big factor in the long range. The GFS implies one setting up toward the SE States as far north as Tennesse well toward 'next' weekend and beyond.

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Sunday, April 21, 2013

Thunder with Heavy Downpours (and Small Hail/Coastal waterspouts Central?) Into Mid-Evening

Explanation Required for image (see below)
As usual, forecast is privy to signficant faults, but will base this one on the previous post of a few days ago despite big model differences between that time and the current time. Over the past 36 hours guidaance indicated that in the previous post where it was alluded to that we could see more rains (Central) by sunrise Sunday, that this would no longer happen. However, guidance is now realigning with that previous thinking, thus, this post will remain with persistence of the previous suppostiion:

TODAY: The surface warm front of the other day is washing out over South Florida and is forecast to invert as shown above in Light Blue (as noted in previous post). This could become a focus with showers or even thunder, especially near the Coast Central and more inland South Florida.  The highest helicity and energy index late today into tonight at this point is forecast to exist across Central Florida at and just offshore the coast along the 2000 ft., slightly 'elevated warm front' which is really only a wind shift line. Further north at a higher atmospheric level is another wind shift line of pseudo-warm front nature at 5000 ft along which mostly rain fall will occur or simply considerable cloudiness.

Impulses aloft will begin to move in from the west and cause the pattern to 'buckle north' in response to their approach. Some will be quite weak, others stronger. Vertical velocities as high  up as 20,000 feet above a only slightly unstable air mass might occur as a result of the energy riding over aloft in a very cold aloft (unusually so), could (emphasis) result in heavy down pours, with a few model runs indicating between 1- 2.5" inches of rain fall coastal Brevard in particular to Southern Volusia County.  Most of these bigger totals, if it occurs, would be due to very slow storm motion if at all long the 2000 ft boundary shown above where there will be little steering. 

The highest instability is expected to remain offshore though (and South Florida), and there will be some steering from west to east. Thus, expect the heaviest activity, should it materialize to remain mainly just off shore. There could be a surprise strong wind gust or surge here or there after 11AM and/or into tonight should large activity send outflow back to the coast from off shore. Also, if conditions materialize such that mid level to low level lift is enhanced, a waterspout might not be out of the question along SE Florida and off Central coasts.

Will note that as of this time before sunrise, the Storm Prediction Center is watching South Florida (only) for strong storms today which very well could end up being the case; however, given the current conditions closely matching up with the NAM (reluctantly), the RAP. and  the HRRR model guidance, will trend in that direction. If the GFS verifies, all calls are OFF.

The implication being, that it is the 2000 ft  'wind shift front" that will be the active parameter going into late day and early evening which is forecast to lie directly across Central by late afternoon if not a bit sooner as the impulses ride in from the west., missing South Florida entirely by that time.  In short, strong storms are possible over much of South Florida although I am only showing a smaller area, and then along the east coast up toward Southern or Central Volusia within 5-10 miles of the immediate coast. Suspect most activity will remain off shore. Those parameters which could result in small hail and strong wind gusts Central might get made up for with heavy localized rainfall instead, should said 'worst case scenario' end up evolving. Off shore waterspouts might become a forecast issue as well for those in the 'know' at the offices.

IN SUM TOTAL: Chances of heavier rain and or storms possible mainly near the coast and off shore today from current time, and again mid morning, and then again late afternoon into mid-late evening.

MONDAY: Rain chances or cloud cover continues into Monday , but rain ends for the remainder of the week. Cloud cover might persist a bit longer.

The more notable warming trend to occur Tuesday or Wednesday with coastal tempered temperatures due to onshore wind off the slowing warming ocean waters, but quite pleasant through the remainder of the week after Monday. The next rain chance comes next weekend as it appears now, but it is way too soon to say with any degree of certainty.

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Friday, April 19, 2013

Chance a Strong Storm Today East Side North Half

As noted above: There is the potential for a strong storm today which could even go renegade briefly severe near the immediate east coast from Brevard County and north after 5pm -8pm. As usual,  even that chance though is in the minutiae
TODAY:  A cold front will be making its way across the Panhandle today and into Central later tonight. Meanwhile, breezy SSE-S winds developing by early afternoon, most notable closest to the beaches with winds nearly parallel to the coast running up the river ways. Just above ground level winds are more south to SSW and then above the mid level curve to westerly with increasing Jet stream level winds mostly late today from the NNW resulting in mid-upper level cyclonic curvature. 

Temperatures aloft will start cold enough for very strong storms but are expected to warm a bit as the day wears on. This alone could offset the chances for  storms but will go with localized coastal affects and potential southward (or northward) outflows from showers and storms toward north Florida to potentially result in added low level convergence that could negate any warming aloft especially along and east of I-95.  Instability is not forecast to be all that strong nor are winds aloft  as they were several days ago on the day of the Tornado Watch. 

Would be particularly interested to see if any storms propagate along the sea breeze frontals  boundary either from the North or from the South today due to outflow propagation, those would be the storms if any occur (in such cases it is usually only one somewhere between Brevard to Ormond Beach) to watch for, which is mostly what this post alludes to.  Given the increasing upper level divergence coincident with the late afternoon favorable time for any shower/storm activity anyway, some showers or thunder could persist until after dark. The Brevard area could also have an added parameter created by the Lake Okeechobee shadow as was the case the other day when early day thunder first formed before the strong storms did.

SATURDAY: Guidance is in agreement that the front will make it to somewhere between Ft Pierce toward West Palm before the parent low well to the NNE is no longer an influence to drag it further down the state. In that regard, best rain chances of Saturday look to be from South Brevard and South, but models have jumped around on the northern extent potentially getting into North Brevard. 

SUNDAY:The boundary then on Saturday night into Sunday gets aligned as a modified inverted trough from S. Florida across Central and North eastward into the Atlantic. By this time colder air aloft will be in place, but also the chance of increased cloud coverage. Regardless, guidance is showing respectable instability mainly across the South half of the state. This, combined with divergence aloft and the presence of the boundary serving as a focal point for low level convergence could perpetuate another cause for more rain/ thunder chances into mid week until the next front approaches changing the game plan again, but there is still a game on going. 

That said, this weekend and into mid-week I'd expect forecasts to vary across the air waves in regard to when and where it will rain. The biggest question mark I can see is Saturday for most of Central and North where it might remain dry mostly.  Not everyone will be getting a lot of rain any one single day necessarily if at all,  but some places could end up with a little surprise package in the rain cage. Temperatures running status quo as those of late with no big changes one way or the other in that regard.  

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Sunday, April 14, 2013

Chance of Strong/Isolated Severe Storm Today - Warm and Muggy

As was the case two days ago, some high clouds Central might be an Issue Once Again
for the amount of rain/storm coverage as well as storm strength. On the other hand....
TODAY: A warm front at the surface is lifting north from the previous day's cool frontal passage which issued in northerly winds. In turn, winds will become again more SE-SSE  today from south to north. Some higher dew point air could be moving in toward Central from the Bahamas as bid mid-level moisture may decreases creating a slight mid-level dry slot. Exactly how deep that dry air is will be one parameter which could determine if the stronger storms (if any) have the uplift to punch through to higher heights and meet the bulk speed and directional shear aloft as noted on the latest SPC Mesoanalysis tool. The east coast sea breeze has yet to set up, but should do so fairly shortly as of noon time.

So far, the better chance of storms will be just inland of Stuart and north toward Volusia county well in from the coast (to start with). Where the east coast sea breeze with a depth of 2-3000 ft stacks up against prevailing SW-West winds aloft across Central to North Central and parts of Central South seems to be the most likely areas to be watching for storms in areas such as Eastern and Central Osceola County to the Brevard County line south toward Vero Beach and Ft. Pierce/northern Okeechobee County and north to Central Volusia County and inland to Eastern Lake and Orange Counties.  

Temperatures aloft are cold enough for small hail and wind gusts toward 58mph should any strong storms develop to severe levels although there is no real pointers indicating that will be the case as of this time. But, things could change for the more likely case or less likely case as the early afternoon wears on. Thus, this is only a pre-fab heads up.  But, interplays along the late afternoon retreating sea breeze boundary combined with any possible earlier activity could result in some short lived briefly severe popcorn; and should "said storm" penetrate the seabreeze toward the east coast  from Brevard to Jax mostly, it could get interesting.  

This as usual is worst case scenario, remembering that just two days ago the same held true, but as it ends up this day might prove to be a bigger challenge for official offices and TV networks since there is not big glob of storms in the Gulf sending a shield of high clouds this way, especially over South Florida and South Central; but with all that has said, IF the worst case can occur, be alert toward US1 after 5pm if any strong storms can press east to the river ways up and down the east coast. To be fair, the NAM model is showing nearly nothing except over the west half of the state due to that the east coast sea breeze in that depiction is expected to get across the state before storms initiate. In that regard, the forecast is a gamble.

Parts of Northern (South Florida) could get into the game as well near the Big Lake. It rained over 4" in a few select locations in the Miami area yesterday, but not from a severe storm.

MONDAY: Again, a chance of thunderstorms although much that occurs tomorrow might be contingent upon what if anything happens today. Any activity appears will be west of I95. Muggy and Warm.

BEYOND: As noted the other day, we will be in an eventual drying trend until late week with some storms possible closer to the west coast from Sarasota and north. Warm with inland highs in the mid-upper 80Fs and closer to the lower 80Fs to upper 70Fs east of I-95 due to onshore flow off cool (but warming) ocean waters.

NEXT SATURDAY Time frame in general looks like it could be another rain maker or cloudy day threat,

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Friday, April 12, 2013

Chance of Isolated Strong Storms Near the East Coast , Warm and Breezy

As noted above with quite a few conditional caveats
TODAY: Dewpoints in the 70Fs !! Zephyr Hills last hour had a dewpoint of 77F degrees with other readings ranging mainly from 70-74F along and south of mainly I -4 and north along the east coast. Compared this to winter dew points  ranging in the 20Fs-40Fs most often.  SSW-S winds could become breezy into mid-afternoon, more so than currently near open waters. The Convective Available Potential Energy (CAPE) right now is the highest we've seen in months since last year approaching 3000-3800 J2/kg2 per SPC surface mesoscale RAP formulae (in winter it is less than 500) with lifted index around -7 to -9C (in winter it might be -1 or -2C), and low level moisture continues to stream north from the SSW; however, there is quite a mid level dry slot in place as well over all but SE Florida  and the panhandle area last hour. That, accompanied by cloud cover from storms well out in the Gulf could shut off the caboose on the storm train today except from near Ft. Pierce and south, but last hours satellite loop does not indicate any thickening will occur, if anything, the clouds appear to be thinning or at least trying to. Additionally, temperatures although very cold now are shown to warm later in the day which would offset the mid level lapse rates currently in place. Still, mid-level dry air accompanied by down draft Cape with little convergence boundaries might make it difficult for storm to initiate without a good trigger.

Thus, this post is a worst case scenario, but things might not materialize hardly if at all except toward SE Florida.  The strongest storms though should be those that are on the move to get off shore the East Coast, Mainly near or just north of the Cape area and south, especially near any NE slated Lake Shadow near or just south of Vero Beach to Ft. Pierce, and then on the other side of the shadow effect near West Palm Beach and south toward Ft Lauderdale . Should said storms develop, especially after 4pm -5 pm, gusts to 50mph are possible and pea hail momentarily. The conditional caveat, of many, is that guidance indicates instability will decrease after 2-3pm as winds remain from the SSW-SW without a sea breeze element for low level convergence playing into the mixture. However, areas near Brevard might start playing with a parallel-side shore element to those winds which could make things a bit more interesting as any storm might develop. It could be that strongest activity would not manifest, if it does,until off-shore. Guidance suggests the further inland activity though will be from Ft. Pierce and South.
Again, as it stands now, this is the worse case scenario. It is possible there will be very little activity, especially Central FLorida.l

TOMORROW: A frontal boundary from the NW will lay out across Central Florida near the 528 Beachway or just south of there toward Vero Beach during the day and then begin to lift back north toward I-10 over night into Sunday.  This boundary could act as a focal point for showers and some thunder anytime almost after noon time on Saturday through Sunset, or simply instigate a lot of  bugger cloud cover. Continued warm, tempered down by clouds. Also, quite muggy once again almost like summer, but not quite that muggy.

SUNDAY/BEYOND: Thunder looks to be in the equation, especially for parts of Central and North closer to the boundary which will remain north. On a course of uncertain time, likely by Wednesday, the moisture surge will end and things will dry out. Most activity should be a bit inland west of I-95 though except perhaps one of those days and be fairly isolated except during the 5-8pm time frame in a few areas north of Orlando and SW toward south Tampa Bay or Sarasota area where west coast sea breeze activity could rumble along.

Otherwise, warm weather and more moist for the most part is in the picture into or near the last week of April. Looks like we can tuck the muck- (bad) lucks  away and winter scarves and hoodies. Summer isn't far away now.

SIDE NOTE: The hottest potential time of the year is from mid-May to the first 10 days of June. During this time is when it is most likely, if it's going to, that Florida sees its upper 90F to lower 100Fs readings, which means one month from now or so. This never happened last year but did the previous two years. 1997 and 1998 were also a big years for the heat. 

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Thursday, April 4, 2013

Threat Thursday - Strong Severe Storm Risk Involved

Complicated Looking Graphic Explained Below

CURRENT: As of 7:30AM a developing warm front is lifting north across Central Florida. This boundary is expected to lift into extreme South Georgia by  the mid-afternoon hours. Otherwise, increase multi-layered bulk shear down to the lowest atmospheric levels is not expected to be in place across South and Central Florida (specifically) until tonight. Cold temperatures aloft are a 'go' as is the forecast Convective Available Potential Energy (CAPE) around 1700 J2/Kg2 (which is not overly impressive at all) coupled with helical spiraling wind flow streamers (helicity) in the surface to the 3KM levels to be in place by noontime spreading west to east across the state. Moisture is a non-issue, especially along the warm front today and along a pref-frontal trough tonight. Low level helicity could be magnified along the entire east coast.

OVERALL OUTLOOK: Refer mainly to the region bound by the DARK blue lines and the white squares for daylight hours. This is mainly the north half of the state.  Skies should clear some by late morning as one of (at least) two impulses approaches the west coast. By virtue of the warm frontal boundary alone, there is the potential for rotating thunderstorm / supercells near this boundary as it lifts toward JAX. Elsewhere south of this boundary, all of the guidance indicates at least a somewhat 'side shore - up the coast' low level surface wind component to come into place as daytime heating commences prior to approach of the first major impulse from the west. Therefore, per this post, I'd consider those white squares to be MDT RISK areas (moderate) as opposed to the SLIGHT RISK area the entire state is currently under and bound by the purple lines.
            High Speed Dirt's 
             "Sky Sanctums" Makes No Claims  
The views expressed herein are those of the author and do not necessarily represent those of the National Weather Service or affiliate/related organizations. Please consult .gov sites for official information”

Note, there are TWO squares along the east side. One is for daylight hours, the latter for late overnight to very early Friday morning (the southern one). Also note Brevard County/Indian River/ S. Volusia in general fall in both regions for both daylight and overnight.

In General, some discussions I've read are stating it is the GFS model all along that seems to have the best grasp on today's overall situation as best can be determined this early in the day.

DAYLIGHT: Warm front lifts north and convective instability (CAPE) increases. Wind profiles would support some rotating storms along miso-scale boundaries amid meso-scale parameters     (namely, the warm front), the secondary miso/meso boundary being along any sea breeze that might happen to form. These 'could' be enhanced up river ways as storms move from West to East. Thus..special attention to the regions along and east of I-95 for RAPID CHANGES in storm structures as they penetrate the sea breeze at the lowest atmospheric levels. Note that this is not to count out regions further south during daylight nor anywhere inland.

TONIGHT: Here is the shift of another sort. By night instability decreases but upper level divergence as the South Half of the state mainly falls increasingly under the left exit region of the upper level 120 kt, 250mb jet stream as it lifts out in side- swiping  fashion. The down player for rotation though at this point is winds start to become more unidirectional with height at lower levels. 

Again though, any activity that might be strong and move offshore could result in outflow back to the coast as they move offshore (in theory only) once again magnifying locally low level helicals (helicity values). Tilted horizontal corkscrewing winds pulled up vertically by upper level divergence could again tilt those spiral into the vertical result in rotating updrafts within embedded thunderstorm structures with little notice.

Current as of blog post with highlighted areas to watch. Again,
along the east coast 'could' in my mind be considered a MDT RISK
area  if the side shore wind and/or sea breeze develops along the east coast

In Summary, best be advised to take responsibility and accountability to monitor Local Television Networks in order to remain abreast of this ongoing and actually yet to actually develop potential weather situation. As always, tornadoes can develop with little or no warning (a tried but true reality).

THREATS: Do note that the SPC is a bit of at the mercy of whatever will or will not occur today and tonight  more so than usual as opposed to larger scale potential severe weather events that normally occur in the more tornado prone areas. This is not usual for Florida. There are times when a threat is in place and not much of anything happens. That is why it is called a Slight RISK area. There is a RISK. In a Moderate RISK, the risk appears to be higher under conditional situations like this one. In short, today's weather situation is highly conditional although looks at the same time fairly certain that somebody somewhere will get socked with a nasty storm, if not more than one over the same location.  If the situation develops as expected a tornado watch or more than one could be issued during the course of events for the more certain areas. And, if storms develop that are within those watch areas, warnings would be issued for specific storms.

Threats include quick spin up tornadoes, perhaps a bone-fide few  from longer tracking (lasting) rotating thunderstorms (supercells), wind gusts to 80mph, and golf ball sized hail (although it has been my personal observation that hail larger than peas does not occur too often in such set ups over Florida).

The risk quickly ends from north to south tonight and over night with North Central in the clear just after sunrise and working south with time. 

BEYOND: Pleasant weather with a chance of rain re-emerging perhaps around Thursday or Wednesday. The GFS is hinting at a QLCS Squall line in about just over a week from now already.  

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Wednesday, April 3, 2013

Severe Threat Thursday - Isolated "Strong" Possible Today

Extra-Generous on the 'Strong" Storm Chance today
But Conditions Warrant a Whisper in the Ear
TODAY: There is forecast to be sufficient instability today propagating from South Florida and just offshore toward East Central Florida later today. Lack of greater coverage though is problematic as well as how much instability there will be,  but this could be offset by cold air aloft and gradually increasing mid-upper level wind profiles with some turning as well which in and off itself promotes upward storm growth in the presence of slightly diverging wind fields well aloft. There are hints of 3-5 storms between the Brevard County zone just inland toward St. Augustine but high clouds further north might negate that potential. Storms or rain showers could continue until after dark ending after 8 or 9pm. Most areas will not experience much if anything today.

THURSDAY: Not much of a change from the previous post, at least as POSTulated. Guidance per the NWS continues to indicate a disparity in timing but that models are coming closer together in regarding to timing, and it is likely this will continue to manifest with subsequent model runs. As is often the case, the reality of the situation will be revealed as the actual situation(s) unfold Real Time, considering that often interactions occur which tend to blur the lines of science with reality. 

NOTE: This outlook extends further South than OFFICIAL OUTLETS
are announcing as of the time of this post

After a break from any potential activity that may or might occur this afternoon, the meat of the matter starts to go through the grinder in the Gulf to approach the state very early Thursday across the Panhandle and then spreads south and east during the day from mid-late morning through the over night hours. The potential chance of strong downburst winds embedded in line echoes and miso-scale rotation in liner like storms on radar coupled with greater mesoscale rotations both discrete and embedded within arcing segments  might result in a Tornado Watch Issuance to the North and then be extended toward most if not all of Central Florida contingent upon how the stage is set and the play acts out. This is noted by the overall chance of that chance within the purple bounds above.

**NOTE: It is HIGHLY recommended that if the situation does indeed develop to any degree resembling said discussion, that access to continuous live radar as opposed to the Weather Channel be partaken with. Some news Channels will likely be on continuous coverage if the situation manifests to a degree that it will be warranted.

FRIDAY: Activity 'might' develop into a more bona-fide QLCS squall line for a time across parts of Central or South Central and press on South and weaken as upper level support pulls off to the East and NE by or before sunrise to early afternoon before reaching far south Florida. Too soon to say for sure IF and when when this will occur, and if so how far such a squall line will extend South as at time such situations create their own environment not foreseen by model guidance.

BEYOND: Mainly dry with only a day or two of mildly cooler temperatures but still well above our last cold spell. Another Severe Weather Chance might manifest once again in about a week from Friday.  

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Tuesday, April 2, 2013

Thunder Possible Wednesday, Potentially Strongly Severe Storms in Two Waves Thursday ?!

Preliminary Outlook (for blogging purposes/not official) For Wednesday
Orange shows thunder chances. Given the cold air aloft, we MIGHT be in for some surprises on Wednesday due to some hail
TODAY: Quite pleasant. What we see is what we got. Winds eventually becoming more SE today with highs in the lower 80Fs inland, with a few mid-80Fs ,upper 70Fs more likely right at the beaches.

WEDNESDAY (Image above): Low pressure will be forming along the Northern Gulf Coast near Louisiana. Meanwhile winds SE at the surface but quickly shifting to West in the mid-upper levels. Upper level temperatures are very cold tomorrow, but lack of deep moisture and low level instability could limit storms to the interior whereas showers could end up moving offshore in at least an expanse shown above if not further south. Thunder could roll off shore the east coast from the Canaveral area and north as well, but it seems more certain along convergence boundaries inland.

THURSDAY: Interesting scenario continues to unfold per consecutive GFS model runs. Forecast discussions which address the ECMWF model of which I have no detailed access to are addressing timing differences and issues which could make a world of difference in the forecast in regard to storm intensity; thus, the precursor comment to not go unsaid is that this blog post is based on the GFS model trends over the past 2 1/2 days, which measa generally nearly 9 model runs.

There is a chance that mid-afternoon storms could form and move in along the west coast from Tampa and north, mainly along and north of I-4. Wind fields above the ground will be becoming stronger with increased helicities values as time goes by and upper level support moves in toward and after dark. 

Nevertheless, air aloft unusually cold with curving wind profiles and increasing shear could result in some surprisingly strong to severe storms later Wednesday afternoon mainly along and north of I-4 with an isolated one or two yet further south. Such said storms will have no problem moving right along and not die off quickly as would be in the case in the summer.

Otherwise, greater 'wind energy' moves in after 10pm for a possible second surge of activity. Now, it is possible this will end up being an Event Before the Event situation, where the stronger storms end up being earlier, but so far given the winds this does not appear all too likely. If the latter event (if there is two or even one, at all)..there could be a tornado watch issued across the peninsula as deemed necessary as more and more recent forecast information becomes available. So far, there has been consistency of which most highlights in my mind at least an area spanning from near to just north of the Central Dividing line and north for a tornado threat, possibly coming out of storms in the form of broken bow echoes and rotating isolated activity early on.

Later Thursday evening a QLCS Squall Line which is pretty much a fancy acronym for a broken squall line containing some discrete storm cells, could start to form, but again much of this is entirely speculative and likely over-amped on the blog posters part. Instability is lacking, making this a chance for a high shear -  low CAPE set up which is difficult one to forecast with as much certainty would there be more instability at play.

Bulk shear is showing up at the lowest levels (unusual for Florida clear up to 20,000 feet at least) accompanied by very respectable upward vertical velocities regardless of the lack of CAPE and low level instability.

Do note, that the Storm Prediction Center is saying very very little about Thursday at this point, so chances are this will be a pre-emptive Strike Out in the forecast game. For now, the pitch hitter is at bat until it is more clear as to how the cards may fall and who's on base.

BEYOND: Rain chances end from NW to SE Friday ending Dead Central by noon but likely sooner and South Florida by mid-late afternoon. Stronger Storms possible mainly South Florida on Friday from late morning through mid-afternoon. After Friday, a drying trend sets in with slightly cooler temperatures but nothing unusual returning to the normal range in the matter of a day or two. 

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