WEATHER MADE CLEAR FOR ALL TO HEAR

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

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

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

Tuesday, July 31, 2012

Variation of Monday in Progress - Showers and Some Thunder Possible

Thick Lipped Arcus Cloud/Storm Gust Front over Canaveral Warehouse
ANOTHER DAY OF 'DOMINO CHAIN REACTIONS' AND POCKETS
OF DRY AIR GUARANTEES  "NO GUARANTEES". Example chances of storms and perhaps something stronger in red but best chances of thunder in the green bounds (although far South Florida could see a very strong storm in no--man's land
TODAY: Different version of the same thing of what occurred yesterday is at hand. From image above, it can been seen a large MCS (Mesoscale Convective System) has dropped across the Panhandle already earlier than yesterday and the west coast sea breeze in broken zig zag fashion has initiated, all the while a line of showers is forming across North Central. This is similar to what occurred yesterday, but the MCS is much bigger and earlier than yesterday's event. Other wise, the east coast sea breeze has too set up south of Daytona.


Thus, we have outflow from the initial MCS, both sea breezes, and Lake Breezes to contend with in an afternoon that is not exactly atmospherically filled with abundant but nonetheless ample enough moisture where mechanisms meet. Additionally, chances are that activity along the North Central line could send off an additional outflow boundary south and east , thus some areas might circumvent rain altogether across Central with the exception being, or rather, the mitigating factor being rain cooled outflow and enhanced clouds over-passing some areas instead of rain. Exactly where across North Central into Central the outflow(s) will cease will determine who will receive the next shot at rain and storms heading toward 4:30-6:00pm. The region from South Brevard to the eastern shores of Lake Okeechobee so far look more favorable today as opposed to further north with the exception of the Titusville region once again toward Port St. John. Steering toward the NE looks a bit stronger today as outflows work south but really anywhere from Southern Volusia to Ft Pierce have a chance for a storm with some stronger gusty winds.  The other area to watch will be toward the Everglades and eastward into perhaps parts of Palm Beach and Martin County (otherwise).


WEDNESDAY: Looks like yet again day 3 of the escapades cycle similar to today and yesterday, with the exception of the unknown storms to the north forming which have been the catalyst for the forecast further south this week in regard to stronger activity. There is a chance again of activity tomorrow, but exactly where and why will be the question, same with Thursday.


BEYOND: Tropical wave could affect all parts of South Florida on Saturday toward the Cape but the bigger impact looks to be statewide starting early Sunday working toward the west side by late afternoon, after which point we could be in for a complete change in the weather pattern and an end to east side thunder. This is a recent 'future-cast development' though, so at this point looks best to take it as it comes.


In regard to tropical activity, nothing big showing up in guidance (yet) other than that there is a noted area in the mid-South Atlantic which could end up crossing the Yucatan, but at this point pure speculation. Guidance nowhere is showing anything strong to form, but more could be on the way. We should be entering a more active tropical period though in the coming days as we enter August, although 'more active' is relative to what we have now which was close to zip. Guidance shows more energy coming off Africa, but nothing close to home. This too though, changes off and on , but no true 'threats' worth noting are being speculated even out to 10 days.

Camera lens fogs up with moisture locked inside due to humidity level changes taking from a cool inside place to warm moist outside place. Cape Canaveral on Monday afternoon.

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Monday, July 30, 2012

Thunderstorms Occurring Now and into Early Evening

12:45pm Radar and lightning depictions are showing lightning strikes with all activity over the Northern 1/3 of the state. Sea breeze related activity has yet to get started. Drier air now in place across Central will be the make or break question later today as outflows and boundaries from the north could 'dynamically' provide the necessary last ingredient for some stronger storms toward Brevard and Martin/St Lucie/or Indian River County near the Lake/Sea Breeze boundary
TODAY: Continuing to play hopscotch with the fickle mid-level trough and now surface boundary across North Florida with the 700mb trough shown (and forecast to) inch just a bit further South and East today providing for better steering toward the east to Northeast. The factor toward Southern Volusia outside of the predominant steering is whether outflows from current activity will work toward the slightly drier air Central and meet up with the sea breeze front which appears will stick very close to the east coast today east of I-95 or near it.  The situation   raises an eye-brow of contentious curiosity but nothing definitive toward the red areas (namely Brevard), but the most likely of the three appears to be the Everglades area. Areas of rain showers are also possible anywhere but very isolated, as is thunder other than that shown in orange (but very isolated). Coverage looks extensive currently though, and mass amounts of rain cooled air could sink southward from where the current activity exists with no problem for activity to spark continuously southward through late afternoon. The question mark being what happens when drier air is reached? Will it mix out or add fuel?


TUESDAY/WEDNESDAY: The 700mb trough should begin to weaken, as such so does steering as we resume a pattern not unlike the past several days, running the 'day by day basis' of the when and where game once again, but isolated. Most assuredly North Florida though as the moisture ribbon works toward Central appears to be the most likely zone, thinning out along the way.


Radar superimposed with the 700mb (10,000 foot above ground level) features shows dry air all of Central South 
MEANWHILE: The ECMWF model shows at least two disturbances (and has been for two days) to roll westward along the Southern Atlantic, first toward the Puerto Rico region toward Florida but that 'track' of this wave changes. The more pronounced item is still further to the east yet still half way to Africa at least. One shown to stay south, with the later shown to curve more WNW-NW with time in the general direction of the SE U.S. We should be hearing about both of these for the next week to 10 tens (and possibly yet another) in some form or another, with a 'storm name' possibly emerging in the next 4-7 days. 

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Saturday, July 28, 2012

Same Old Story, Different Hat

Same old story - "It might rain here or there but not everywhere. But where is anywhere? Somewhere"

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Friday, July 27, 2012

Chance of Isolated Thunder after 4:30pm (Until?)

Moisture from SW Florida where showers now reside should be able to snake its way north and east a bit through early evening in the lower 8000 ft with self-manifested by earlier showers themselves moisture higher up along the sea breeze convergence boundary Eastern toward Central interior by late afternoon. The west coast sea breeze is already pressing eastward as of noon time in a broken uneven fashion so timing will be critical factor today in regard to how, where, why, and when any storm (s) will or can manifest 
TODAY: Beyond the mud, the 700MB circulation manifested yesterday as an MCV (Mesoscale convective vortex) over the Northeast Gulf has opened up, and appears to be getting slightly nudge eastward as a result of temporary troughing further north as a result of a front that pressed through the Northeast States yesterday.


At the surface, the low level ridge axis remains across Far South Florida with low level moisture feeding around its stronger western periphery along the SW Coast and as per guidance will be pressing NE ward during the day. Latest analysis is showing sufficient moisture in place from SW Florida to North Brevard in the lower levels, but  above those twoard 10,000 feet it is quite dry in all locations except in the western Panhandle. The west coast sea breeze has already begun and seems to be taking off eastward faster than would be normally expected, perhaps due to the 700mb trough actually pressing east just a bit. In any case, beyond that mere speculation the greatest instability today is unevenly dispersed with the only consistency being just along the Atlantic Coast. Chances are, more low level moisture, hence atmospheric buoyancy will be lifted North and East as sea breeze circulations meet and squeeze moisture NE ward along the 850-700mb flow.


With those rough and sketchy depictions showing on models, some thunderstorms and showers should be spreading NE ward from the South as the afternoon progresses with an isolated shower or storm possible toward Western or Central Volusia, although that one is the big question. What seems a tad more certain is thunder and showers working as far north as I-4 in the Orlando Area and eastward toward the Eastern Osceola County area and possibly showers and thunder almost as far east as the Sanford into the Mims or even Titusville area by 6 or 7pm. This all being the 'worst case' scenario for those not wanting their picnic rained on.  


The graphic shows one general area where a stronger storm could exist due to down draft winds..a result of the dry upper levels cooling upon decent into the more moist air in thunder or even heavy rainstorm down drafts. Temperatures aloft are not all that cold, but any storm (if there be one) that punches through the dry layer on its own devices along converging low level wind fields  could put on a spectacle, then back trace southward beyond dark into Osceola County. "Could" being the operative word in all cases. The final 'could' or 'might' is thunder after dark south of Orlando. As noted earlier, all of the above depends upon when the sea breezes meet. If it is too early, all bets are off.


BEYOND: Saturday looks a bit like a variation of today with Sunday through Tuesday going up and down on the rains chances near these same locations as time will tell.


WEDNESDAY: As would be expected, it is summer and the dry air cannot last forever over Florida (one hopes).  Moisture only increases or varies in small increments from day to day into Wednesday but from there on out the GFS and the latest ECMWF (Euro) indicate a tropical wave to cross near Puerto Rico and arc NW toward Florida (previously the ECMWF was showing a possible depression but is now amazingly close to the GFS, which given that is a good 5 days away is sure to change several times if only over the weekend).


 In any case, per what is given today, increasing rain chances Wednesday but much more so toward NEXT weekend for a few days with two moisture surges.

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Wednesday, July 25, 2012

Warm and Hazy South, Variation of Yesterday Elsewhere

 Taking the camera from A/C to warm humidity late yesterday to capture an image resulted in 'moisture on the lens'. This Cape Canaveral , Florida Arcus Cloud trended toward being a Shelf Cloud due to the close proximity of the actual rain field, meaning little time for outflow separation. Rain field seen bottom right corner of image. Thunder boomed with lightning very near by at this time.

Radar image from Tuesday is interesting. Note how activity hit the sea breeze over the Banana River and quickly 'jacked up' per yellow through red actuals (not drawn in). Most lightning was toward the Industrial Area and the Pads out at the Space Center

TODAY: Somewhat a variation of yesterday mainly north of the Pineda Cswy in Brevard County west toward the South end of Tampa Bay.  The better chance of storms, some quite strong to marginally severe along I-10 and other zones in the Panhandle toward Tallahassee and a bit east of there.


Further South, trough in the mid-levels dropped south just a bit from yesterday but is slowly loosing identity. The axis extends currently along to just south of I-10 but could drop as far south as the Beach Line by 5pm. Guidance is trending that way at least on the short term RAP model, and the GFS from 2AM seems to be hedging in that direction since the 2PM run yesterday. Based on the latest Analysis a good west coast sea breeze appears to be in the making dynamically speaking which would fuse eastward fairly rapidly not unlike yesterday, with the southern end lagging a bit toward North Brevard or even Central Brevard. For now for that entire zone, showers mid-day might be more in the making toward the interior but tough call regarding the thunder here (interior) due to the unfavorable time of day during peak heating when lifted condensation levels are 'normally' a bit 'elevated' as is the level of free convection. On the other hand, with the latter time of the day being preferred the further east one looks, the I-95 to US 1 corridor could be the better breeding grounds for thunder with low level forcing created by the coast hugging sea breeze. For now, It appears it will make little lee way beyond US1 up and down the coast.  Showers and any thunder will roll off the coast uninhibited, with a "Tail End Charlie"  storm possible near the Space Center toward Port St. John,  Port Canaveral and Titusville area across the Merritt Island Wildlife Refuge. It is tempting to draw that zone a bit further north though, as short range guidance waves up and down north and south. In short, it appears it will all come down to timing issues so there is no point in musing further.  Further south, showers and maybe a rumble are possible to Sebastian in quick passage.


SOUTH FLORIDA: Haze appears to have moved in based on satellite imagery and moisture at all levels necessary for storm formation appears to be sorely lacking. However, the forecast office down that way and another office are watching the Lake Okeechobee area toward Ft Pierce to West Palm once again (where some strong to severe wind reports came in yesterday in that county).

BEYOND: Dry air from the North and South closes in as rain chances dwindle to negligible to down right zero  in an unusually dry pattern atmospherically speaking for this time of year except far North Florida toward possibly Flagler County. Moisture rejuvenation begins Sunday toward SW Florida working North and east into Monday when storms could form into Central Osceola County toward Brevard, but further North seems to be getting the dry side of the coin. 


Better rain chances yet still though Tuesday before Wednesday where better coverage in the 40% forecast range might be getting closer to home for most forecast offices..

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Tuesday, July 24, 2012

Strong Wind Gusts/ Lightning Possible Near Beaches in Any Storm

Arcus Cloud or sometimes referred to as a  'Gust Front'  from Leading Edge of Rain Cooled air mixing with the sea-breeze (above) at Cape Canaveral on Monday. This 'front' extended well to the South and north as well

TODAY: Mid-level low is positioned over the NE Gulf and appears will drop southward just a bit during the day before eventually eroding through Wednesday. Meanwhile, low and mid level ridge axis is across South Florida . Between the two a general WSW-SW flow is at hand as expected with a shallow sea breeze having penetrated coastal communities from Miami to at least as far north as Cape Canaveral running up toward the Industrial Area on the Space Center. An area of showers that was over the waters off the coast of the Big Bend and south appears to have collapsed and sent an outflow boundary of rain cooled air eastward and is now manifesting as a line of showers and some thunder as well. Strong activity does not appear for the most part to be at play with this activity.


Further south from near The KSC along the east coast is a different atmospheric story where mid-level dry air (especially south of Melbourne) but respectable low level moisture is generating some storm activity along the Lake Breeze and near shore waters, seemingly as a result of outflow from an offshore cluster for storms early on.


In summation, prevailing SW steering to meet the sea breeze very close to the coast in an environment suitable for an isolated storm or two containing some wicked lightning and brief strong winds, but this activity might for the most part move rapidly offshore after developing if it does at all. Stronger activity, IF there is any are noted in red as a starting but not all inclusive example, especially after 5pm. Weather permitting.

Image showering rain-cooled outflow near Big Bend by dashed yellow. In orange any thunder will be very isolated, but as boundaries interact there could be momentary but brief increases in lightning or coverage during the afternoon.
Enhanced Progression of the west coast sea breeze from the outflow puts activity south of SR528 a bit later in the day than further north with a chance of a 'freak interaction'  somewhere from Port Canaveral, Port St. John, Titusville, Launch Pads zone if not a bit further south.  Already activity in place further south with boundaries to approach far South Brevard and the general West Palm area. Any activity near Miami and south if it can manifest could be strong, but this area might clear out too soon with the west and east coast sea breeze meeting too early on in the day.

"Arcus Cloud" Some Might Call This, Other's A Gust Front (non-technical term). Port Canaveral on Monday. "Shelf cloud" would technically be incorrect.
BEYOND: Much drier air to below seasonal norms over the Florida peninsula through the mid-levels with warmer than normal east coastal and east side of the state temperatures to prevail with delayed sea breezes each day, or perhaps none at all Wednesday and/or Thursday. Chances are though, the zones along US1 toward A1A will find the relief by noon time or so with inland zones not catching a break.  Any rain or storm activity (isolated at best) will require late afternoon to early evening sea breeze convergence to even materialize except along I-10 which will occur closer to the east coast than usual. This appears will remain the case through the weekend at the rate we are reading now.
Through The Lens under the whale's mouth of a Florida East coast thunderstorm

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Monday, July 23, 2012

'Possible' Strong/Very Strong (Isolated) East Central)


Quick post today due to time factor . Area of showers and thunder is approaching The Center of the state in the midst of on-going activity as noted above. The area in South Central is moving NE-ENE and heading toward a CAPE gradient boundary aligned from near and east of Kissimmee or mostly the entire east half of Osceola County, Eastern Orange, and Seminole with a direction poised toward the coast where instability drops off due to earlier cloud cover. Models were in zero agreement today for the most part as a low in the NE Gulf almost down to the surface moves little (appears that way). Mid-level winds are from the SW-WSW over-riding low level SE winds right in the high CAPE zone, so a sudden eruption "Could" occur in the western most red zone in the next 90 minutes or so. Much will depend on if the activity collapses or loses upper level support, as it seems to be getting triggered by something aloft such as a vorticity lobe not shown in guidance. Thus, areas from  mostly of Orange, Seminole. Osceola Brevard, and parts of Volusia might need to have a heads up alert in the next two hours or so. If the area holds up, might need a renegade warning or two..OR..it fizzles to mere rainshowers.


TUESDAY: So far, good consistency up to now for an interesting day taking shape mainly for the East 1/2 of South Central from Melbourne down to Ft Pierce including the Vero area mid-late afternoon.


BEYOND: Much drier, most activity along I-10. Also, much warmer at the coast before the sea breeze, possibly hazy with an isolated late day or early evening sea breeze collision type "something or other storm" near or east of I-95. Low rain chances into the weekend .

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Sunday, July 22, 2012

Unusually Warm This Morning, Storms and Shower Issue at Hand

Water Vapor Image showing moisture at mostly mid-upper levels.
The more color, the deeper the moisture.
Highlights on animation show what appears to be a vorticity max or upper level low like feature near Lake Okeechobee lifting slowly northward (the red "V"). Ridge axis (blue) to move little today ,if not strengthen in positioning. Note 'speed max' lower right.  
TODAY: Will quickly compare model guidance for reasons that will become apparent further on in this quip. The North American Model (NAM) and short term Rapid Refresh (RAP/RR) are showing zero rain today except along the west coast mainly. On quite the contrary, the GFS is holding fast to several runs prior with deep moisture reaching as far north as the secondary ridge axis shown in the image above by the small blue 'zig zag'  across far Southern Volusia County. It has depicted this scenario consistently, then again, the NAM has depicted the zero rain scenario consistently as well. 


The Storm Prediction Center and the MLB NWS are in agreement closer to the GFS (and possibly the Euro which I do not have access to) which would favor thunder and showers south of the northern most orange line, or mostly from near Melbourne and South across the state. For now, will side with this line of reasoning given the swirl evident near the Big Lake lifting north. It appears the NAM and RAP are looking at warm upper-level temperatures capping off rising motions (as opposed to cold air aloft), thus preventing rain storms and thunder from forming. In short, we are at the mercy of which witch is which, so in playing the 'Wild Card Shrug' will side in agreement although this in my mind is questionable. There is no doubt the west side will see activity later today, it is the east 3/4 of the state that is questionable. When will we know to go from Two Pair and play a potential full house? Apparently not until after noon time when the tables turn and supposedly the cooler air moves in. But better yet, in about an hour or so morning sounding data will be coming in to reveal the true nature of the atmosphere in place over the state 'aloft'. Unfortunately, we still do not know what conditions reside out over the Atlantic and Bahamas (which is upstream for the state in the current flow pattern).

Otherwise, it is very warm prior to sunrise with 80F on the porch and 81F at Melbourne, and warmer readings further South. St Pete is reading 81F with a dewpoint of 80F which is close to morning readings of "insane' on the thermometer/dewpoint scale if there were such a scale to read . Guidance is showing high instability already in place to persist all day long , with values of Convective Available Potential Energy (CAPE) already akin to late afternoon values, unusually so. Not surprisingly then, it is very humid at this hour since CAPE includes the low level moisture (dewpoint) variable from the equation from which the value is derived.
Big Thunder activity north of Cuba moving WNW

Later today, the GFS has been consistent on picking out a mid-to lower level wind speed max rounding the base of the Atlantic High Pressure Bubble (the axis shown by jagged blue above) with the arrows shown in the first image in the lower right toward the state. These winds will advect straight off the north Bahamas toward Central Brevard shortly after sunset, thus there is a chance that some showers or even thunder could move ashore into Brevard after 9pm tonight for a time due helicity curls off the islands. Whether they will make it onshore (as well as the exact positioning of those winds tonight ) will determine if in fact rain is realized toward the Cape Canaveral area.


MONDAY/TUESDAY: Given the already major question, "Exactly where is the best moisture heading this morning?"!   means as well, "Where will it then be early in the week as well?". Point in case, if the GFS is correct , better rain chances most areas on Monday with the offices showing a 60-70% rain chance, whereas the NAM with its output showing ZERO rain chance! :-0  (aghast emoticon exclamation). Will stick with the GFS at this early hour, meaning much better rain chances with thunder Monday. The ridge axis shown in the first image is then to drop South to the south end of Lake Okeechobee overnight Monday night with a flip flop in low level winds and steering currents from WSW or SW toward the ENE-NE. The moisture bubble gets trapped over Central and North Florida resulting in isolated thunderstorms forming mid afternoon through early evening which would be able to move off the east coast north of Ft Pierce or Vero Beach (more likely) while The Far South remains mostly dry.

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Saturday, July 21, 2012

Isolated Heavy Rainfall Totals/Gusty Winds In Storms Possible Today

Some stronger storms (red) are possible today with big rainfall totals due to slow storm motion and continues inflow feed from coastal sea breezes accompanied by high instability feed in CAPE and Lifted Indices under dry air in the mid levels
TODAY: Gradually evolving pattern taking shape as expected with the usual twists and turns along the way. "The SAL (Saharan Air Layer) has cleared the area~!!"  pipes the trumpet, "all coasts clear". 


Meanwhile, gradually increasing moisture toward just below seasonal norms except South Florida today will result in more coverage of unsaid yet summer like storm activity as opposed to yesterday's "SW Floridians Only" storms and an isolated pocket near Marion/Lake County (for the most part).  Sea breeze convergence looks like a better bet today with a slant favoring the interior with outflows reaching toward I-95 or US1 very late toward dark. Thus, we could see some increased cloud coverage near the coast, especially north of 528 due to mid-level wind directions pushing cloud debris with no other impacts.


Otherwise, increased low level instability and 'forecast' cooler mid-level temperatures (the morning KSC sounding did not reflect these cooler temperatures, so it is a matter of trusting that they will 'advect' or move into the area in 'red' later today). Above the mid-levels, temperatures are cold enough to support a strong storm or so, if one considers -8C which is well below freezing, cold. A bit hard to imagine   air up there is so cold when it is 90F + at the ground. But, hot air rises, and the colder above that hot air it is, the faster it will rise. That , coupled with moist air which is  more buoyant (like steam), adds up to clouds and updraft columns, visible or not visible to the eye. They are only visible when clouds manifest and in time-lapse, except under a growing cloud base, referred to as 'cloud tags' .  Strongest storms after 5:00pm mainly from near the Osceola County line up toward Orlando / Narcossee (maybe), Kissimmee, and much of Polk County as well as further to the SSW where deeper moisture will advect in as the day wears on.


As this activity collapses under its own weight due to slow storm motions, outflows (quite gusty due to cold air falling) could extend well past the west coast and near I-95 or US1 on the east coast with little effect other than some clouds. With heavy rain, frequent lightning, gusty winds, and BB sized hail potentially in an isolated momentary up-burst collapse well in the interior , the immediate beach-goer will remain ignorant to all this occurring in the   after 6pm while innocently tipping the toes in the cool ocean waters behind one's back to the west while considering a sea shell.  


SUNDAY: Discrepancy being resolved, but still not quite, as models disagree on how far north moisture will get on the east side of the state as opposed to wrapping south of Lake Okeechobee and up the west side. It's looking more like the rain producing qualifiers will remain from Indian River County and South and work toward the inland and west coast area toward Cedar Key or Brooksville, with the rest of the east remaining dry.


MONDAY: The plot thickens. Will the moisture  in a secondary surge slap a an atmospheric moisture wave ashore further north  ...or is it Professor Plum, in the library, with the candlestick ? Implications are the former will be the case, but with thunder activity inland mainly South Central and South, not too far off from today...will have to investigate this with a magnifying glass more as we work toward tonight and Sunday.

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Friday, July 20, 2012

Remote Chance of a Near Severe Storm Today

"Storm to the West" - 7:30pm Thursday near the Marinas at Port Canaveral

Yesterday a few strong storm  reports came in from activity near Bithlo in Orange County   near Wedgefield and Bithlo and toward the ENE. Much activity that was also likely strong occurred over uninhabited swamp like land, ; one report of small hail also came in. The activity hit the east coast sea breeze west of I95, but managed to progress east toward the coast in North Brevard. Other weaker activity occurred further north earlier near DAB and the Titusville area toward Mims had two shots at rain. A severe report came in that limbs 'the size of a wrist' were broken, but specifics as to whether that was a newborn's wrist or a Sumi Wrestles remains sketchy...the search is on.

 The outflow gust front feature progressed toward Cape Canaveral  and Cocoa Beach.


TODAY: As expected, dry air O-rama in the mid-levels and warm to hot inland in the absence of more clouds and light inland winds. There is not a shortage of low level moisture though with an inversion above ground low enough to preclude formation of big cumulus clouds until later and in-land. SO 'going out a limb' (the size of a wrist) there is a small chance of a storm very late near Lake County as a result of a sea breeze collision which would mount up low level moisture and because low and mid-level lapse rates would be pretty darned strong, it could be near-severe. Any upward momentum that could escalate a storm to the upper levels could end up being fairly impressive but of short life span due to slow storm motion. Any said such event though is highly conditional on other numerous factors.   I see model guidance painting green brush strokes all around Tampa Bay, but given the current tested atmospheric conditions via morning sounding data, would think that either something goes BOOM in a big way, or barely ekes out a drop of rain at all.



SATURDAY: Slightly more coverage of activity tomorrow near I-4 and toward the interior or western interior down to SW Florida and the Glades, as moisture increases and remnant haze clears out.


SUNDAY: Different day entirely. Latest guidance is a bit askew concerning when deeper moisture will work north beyond South Florida. Southerners  might be seeing showers south of the Lake before 10AM if not at sunrise, with activity progressing north through mid morning and early afternoon. Whether or not the immediate east coast north of Indian River County gets wet is even sketchier with model timing differences as big as a full 12 hours. Thus, Sunday afternoon at the beach north of Vero or Ft. Pierce might not be all so bad after-all, with the better chance of rain not arriving until after dark.


MONDAY: Pretty good chances of showers and storms almost state wide with the east side seeing activity with some lightning just about any time beyond 1PM in the afternoon, Hard to say for sure.


BEYOND: Another slot of SAL might come in taking rain chances down to isolated Tuesday through Friday.


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Thursday, July 19, 2012

Chance of an Isolated Strong Storm Late Today near the Coast

Albeit sketchy at this time of 9AM....
TODAY: As expected, dry and elevated dusty air is moving into South Florida courtesy of Africa. Expect glared skies with filtered hot and humid air there today. Low level moisture is still quite plentiful though, so expect it will be very humid and hot over all of South Florida especially away from the coasts as far north as a line running from Ft. Pierce to Port Charlotte, but some low cumulus clouds will provide temporary respite.  Further north, the ridge axis (of high pressure) is forecast to remain far enough south that chances of quick showers are possible in green. Latest guidance in one model shows storms possible toward the SW coast (however). 


**Side note, yesterday wind gusts were measure in the 40-51mph associated with the storm/storms over North Brevard from Canaveral toward the Barge Canal.


Otherwise, extensive cloud cover is over the North half of the state so not really looking for significant storm activity north of I-4 today. Further south, low level instability as a result of that buoyant low level moist air under the dry mid and upper level air will mount and advect toward Central Florida during the day. At time, higher clouds are streaming across Central from the Northeast, but so far those are expected to dissipate by early-mid afternoon. Those will hold temperatures down a tad, but nonetheless, the invisible instability will be present as the day wears on. 


Winds are expected to become side shore or nearly so from Sebastian Inlet and north up the intra-coastals to a bit more onshore north of Melbourne Beach due to the curvature of the cape.  Steering today remains from the WSW at about 15-20 mph.


Any showers or storms that form north could send outflows south into the more unstable air mass which has less moisture content. Thus,any activity today will require the west coast sea breeze to progress 'silently ' eastward accompanied by those winds and into self created moisture convergence at the low levels along the east side of the state. This convergence along with instability advected north from South Florida and better vertical upward velocities (lifting convective motions) and coastal low level vorticity and some helicity could provide enough lift for a few thunderstorms, possibly strong with wind gusts in the 40-50mph north of SR 528 and South of New Smyrna Beach. Would expect little advance warning of any said potential activity (potential being the operative word), as storms could quickly escalate upward upon cross I-95 give or take a few miles. Winds, if such storm could manifest could outflow toward the Port to Melbourne beach regardless if it rains or not and be briefly gusty as well.


Due note, much of what happens late today is contingent upon dissipation of the high clouds in this same area  colored in the more vibrant color schemes through the north central portion of the state. For now, dispelling the SW coastal area near Ft. Meyers beyond low topped showers. 


FRIDAY: Dry ribbon to lift north to Central with South Florida already beginning to recover. Storms possible the west half of the state south of Lake Okeechobee in general and north Florida.


SATURDAY: Dry ribbon begins to fill in, with what appears will evolve into a chance of isolated activity near I-4 late day and toward the interior as moisture increases from South to North. This , so far, appears will be the better of the two day weekend for outdoor/beach related activities


SUNDAY:  Increasing S-SSE flow to advect a moisture surge northward with showers and thunder working up the coast and interior by late morning, possibly starting out South Florida in the early early day.
Or, perhaps this will be more cloud cover than shower activity. Either way, without much sun or much less of it by noon time or so..not such a great day for the beach appears to be the verdict...at least as of now based on model consistency for 2 solid days.


BEYOND: One more dry time into early next week then the GFS insists now (and has been for a week) for a trough to eventually develop a trough running down the east coast along and east of the Appalachians with the gall to eventually drop a front into Central Florida by late next weekend or so, but given the time of year if even so this were to come to fruition in some form, it might make it toward I-10 or I-4 if this , in fact, evolves at all. Hard to be certain, but any high pressure building south from SE Canada ..opens up all kinds of options in what so far has been an atypical summer nation wide.  

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Wednesday, July 18, 2012

Thunder Likely in "Pockets" Today, Especially East Side

Weak Thunderstorm Hovering into Cape Canaveral on Tuesday
TODAY: Short post today due to time constraints. Upper low that was near JAX yesterday lifting NW into Central Georgia as mid level trough that was across North Central weakens and lifts north. High pressure ridge beginning to build into South Florida will result between those two in stronger WSW to ENE steering today holding off sea- breezes north of Sebastian except toward the immediate barrier islands as winds at 2000 ft are two strong for much more than a shallow boundary.


Further south, Lake Breezes along the North side of the Lake and the better chance of the sea breeze east of it could enhanced convergence and storms especially since latest guidance shows much stronger instability being advected into this area off the Atlantic.

Showers with thunder already moving in on the west coast. What effect this will have on locations along and north of I-4 is unknown. An outflow boundary is already noted ahead of these storms showers which will move toward the WNW-NW through the late morning hours into the early afternoon. Convergence might be enhanced over the east 1/2 of the state as heating commenced, but then again, so might cloud cover there.
South of I-4 is where the better likelihood of an semblance of a sea-breeze is possible near the coast but further in from the coast over SE Florida. There is some cloud cover in this area this morning but it is moving around a bit and might dissolve itself by noon time.


THURSDAY: SAL air mass impinges into South Florida by late day and might deter activity most of south Florida but Central and North will not be fazed. Activity will be a bit more isolated Thursday and Friday as the dry air mass lifts north across Central by late Friday or Saturday and further north on Sunday, as activity resumes over South Florida by Saturday and more areas on Monday as it shrinks in size. In short, Central looks pretty dry on Saturday but more active Sunday and Monday.
TUESDAY, Cape Canaveral

BEYOND: Another SAL surge is seen to move in to the state by early next week toward mid-week which will be the next bone of contention.


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Tuesday, July 17, 2012

New Theme, Better Thunder Chance Today?

Two (red) Upper lows remain in place. The one near JAX is expected to lift NW today slowly while the dashed lavender line denotes a mid-level trough axis which will move very little throughout the day. Note the dry, hazy air mass approaching South Florida forecast to arrive toward Thursday/Friday and then lift north across Central on Saturday
TODAY: Hard to say exactly , for sure, definitively, or even probably what will happen when and where today as showers already forming over Western South Central portions creeping NE (but  very weak).  Guidance is pointing toward a slightly better low level instability today, but lifted indices (a measure of instability) could be the clincher, as they have been pretty low the past two days.  One severe warning was issued very late day in Marion County along a west coast sea breeze type interaction.  Otherwise, do expect a shallow east coast sea breeze to form today with a more rapid acceleration of the west coast sea breeze, especially south of Brookesville and south into the interior regions. A late day collision near I-95 is possible which could be the harbinger of stronger storms as noted in red-below.


SOUTH FLORIDA: Problem is activity off the SW Coast. If upper level winds advect cloudiness across this area the rain chances shut down entirely. On the other hand, they could get started early enough and/or those clouds could abate later today, so not to count that area out.


CENTRAL: Better instability is forecast to work in from the NW today across all of North and North Central toward Brevard.  Activity to the north will move very little under and north of the trough axis whereas activity south of it could meet the near coast sea breeze with greater low level forcing. Thus the red line for possibly stronger than expected pulse like and short lived activity, although that of the sort could occur almost any where after 4pm through 7pm. Expect again the first true activity like yesterday to begin to manifest shortly after noon time Central Portions and South., as further north this area is much too stable this hour.


NORTH: Could be yet stronger activity at least the west half of the panhandle region moving offshore. Winds here are a tad stronger, but really, the coolest mid-level temperature 'forecast' is along that 'orange' trough, thus, a secondary reason to at least consider better chances of thunder as opposed to rain showers, especially after 4pm, cloud cover permitting.




BEYOND: More chances of thunder on Wednesday many areas but chances dwindle toward Thursday through Saturday in various areas as the drier air moves in.  By Sunday the drier air might be all but cleared the state with a resumption of storms a bit inland from the east coast for a day or two.

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Monday, July 16, 2012

Wide Spread Convective Showers, Some Thunder Thrown in, Isolated Strong Possible

Graphic shows the mid levels, with two lows in the upper levels. The low over Florida is forecast for this afternoon in the mid levels and should be the primary monitoring area for more robust activity today
TODAY: Pattern continues to morph with our two upper lows slowly working Westward to WNW. A mid level trough will work north to central and north central today and come more aligned with the trough at 20,000-30,000 feet aloft. Weak sea breeze along to east of US1 possible north of West Palm mainly to have any real effects - not, with the mid level cold pool  nearest the low.  Little in low level forcing due to lack of a solid sea breeze collision is a possible downfall, and clouds over the Big Lake of Okeechobee should preclude any meaningful Lake/Sea breeze collision effects given the late time of morning already with no apparent signs of clearing as of yet. Should this region clear by early afternoon, that throws a new wrench into the equation.


For now, any strong storms could be from North Brevard and north toward Flagler County just in from the coast into the interiors, with outflows working south and east and west and every which way. Southwest winds in the mid-levels will steer activity off shore south of West Palm but further north the currents will be too light toward south of DAB (Daytona). There is no steering north of Mims in general and only a drift between that area south to Sebastian by later this afternoon toward the coast. Problem is, activity might get started soon enough that by later today the atmosphere will be worked over which makes further discussion a moot point, but would watch that low pressure area primarily due to some potential vorticity aloft acting as the primary triggering mechanism for actual thunderstorm activity. Winds aloft are very light, so any stronger to even severe storms will be pulse and brief.


TUESDAY/WEDNESDAY: New pattern altogether as the northern upper level low shown east of JAX drifts WNW and gets absorbed into the mainstream synoptic scale flow. Steering SW to NE with greater low level instability means early start to showers and storms almost statewide.


THURSDAY/FRIDAY; Drier air aloft works toward South Florida first then begins to lift north in a  fairly narrow band making late Friday into the Weekend conditional in regard to where storms will exist, with a resumption to more moisture at all levels by Monday (next week) and more SW Flow aloft. In short, typical atmospheric moisture availability will be in play other than late week into the weekend with the atypical diurnal variations typical of outflow west coast sea breeze and lake breeze interactions. Did we just say atypical is typical? ! As usual, some stronger storms are possible on any summer day, so that is not unusual...typically. 
Rough guestimate for starters with red being maybe some stronger activity. Could see some funnel clouds today...there is some gradual clearing toward Ft Pierce, so late day activity could occur in this region. It is left, 'unmarked' due to the abundant unsuitable  at this time situation over far South Central Florida today.
  
 

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Sunday, July 15, 2012

Pattern Metamorphosis To Begin Compiling Today

Preliminary Estimation of best rain chances today
TODAY: Image minus the colors is actual to the best available information location of upper level lows discussed yesterday. The eastern and more northern one did begin a more northerly motion which left the peninsula much more dry that would have been otherwise (possibly). 


Early Today guidance is coming into better agreement though and seems to be changing in the short-term model with every subsequent out put like a compiling computer program trying to reach a point of completion. But it will be never-ending for several days here on out. 


Chances are, after morning sounding data is taken and extrapolated and fed into that model things will change again, but even more so tonight and tomorrow as that trough finally pulls into station. Hopes are that by the end of the day we won't be crying "Wolf!", as this post is a bit 'ad hoc' for all intensive and extensive purposes.  Upper lows to drift west today taking the shown trough located in the upper levels with it and across Florida. There are adjustments in the lower levels as well though, with our easterly winds becoming more SE to SSE mid to late day, and steering becoming more southerly to SSW  south of Lake Okeechobee especially after 5pm as far north as northern South Central (South of the Beachline Magic Dividing Line zone).  Better lapse rates for thunderstorm generation will materialize from SSE toward the NNW during the day beginning mid-late morning spreading to South Central zones by 5pm or 6pm.  Sea breeze convergence, rather lack there off north of Lake Okeechobee, is a mitigating factor pretty much everywhere except perhaps earlier to mid-afternoon activity that might get going near the Lake breeze interactions.


Further north, storms 'could' work north both with and ahead of the trough (s) due to propagating outflows meeting the previously already established east coast sea breeze. A late day collision of sorts could occur over Polk County  or west toward Tampa, but the better instability will remain along the eastern half of the state nearer the trough axis and better lapse rates above,  and most of far Southwest Florida . Since this is a big transition day as highlighted previously, especially toward dark, some activity could continue post-sunset - post dark toward NW Florida whereas other areas might get worked over or in general no longer remain favorable for storms, not to say isolated activity could not re-occur, especially South Florida.


MONDAY-WEDNESDAY: The pattern shift reaches near completion almost never, as the trough continues to move west and into the Gulf pulling moisture northward on its backside. In general though, light SW to NE steering develops by Monday afternoon through the remainder of the week, while the TUTT SAL SALT AIR MASS continues west , now already having infiltrated the Puerto Rico area. Latest guidance has slimmed down a bit on the impacts overall to the state of that air-mass, except toward and south of Lake Okeechobee.  


On the other-hand, lapse rates and surprisingly the GFS shows this,   will supposedly become more favorably supportive of strong to severe storms, albeit quite, quite isolated. Tuesday and especially Wednesday shine through on the GFS, as it rarely shows high degrees of instability over Florida, let alone 4 days in advance.  Central Florida overall seems to be the location for such activity on Tuesday and Wednesday, but no one area will be immune from rain chances through Tuesday or even Wednesday, with activity likely starting out in most robust fashion along the Lake/Sea breeze zone of Northern Palm Beach/Martin/St Lucie/Indian River Counties working northward up a delayed sea breeze.  


It will become quite summer like (as if...), humid, and hot for the beach folks given the delayed sea breeze anticipated. In short, this pattern is a bit rare for this time of year over South and Central Florida, so we can expect the unexpected for a few days here and there and just about anywhere. 

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Saturday, July 14, 2012

Out On a Limb-cast Leaves Options Open this Afternoon

Friday morning at 9AM Shower passing over North Cocoa Beach  

TODAY: Model discrepancy runs rampant from model run to model run and between models in regard to today, and not so coincidentally is not matching up with latest satellite animation trends.


Thus, for the more rain prone (but apparently less likely wetchancecast per latest water-vapor and satellite animation) an upper level with a weak surface reflection well east of Florida and NE of the Bahamas is rolling W-WNW with increased moisture and much larger shower and likely thunder activity with it. Comparatively speaking, small showers on local radars are showing mainly South Central and south that look like mere specks on satellite as we will see below compared what is well off to the east at this time.


 Based on timing via animations, it appears the leading edge of deeper 700 millibar (mb) moisture (near 10,000 feet or so up in the atmosphere) will reach the east coast after 2pm which could mean a much better chance of showers in the zones noted below. On the other hand, should the NAM and not so much the RAP model verify, the moisture will only get so far west before slowing down,   not coming within the bounds of the beaches until at least as late as midnight toward 7AM Sunday. That is a BIG difference . Thus, for a east coast wet-cast, showers could be on the increase by mid-afternoon. On the other-hand, we might be able to hold off until sometime well after dark.


Otherwise, the better chance of showers and thunderstorms will be from Tampa and South within 30 miles of the west coast, with strongest activity downstream of Lake Okeechobee under the largely east to west flow aloft.  The tides and times change though later tonight as the trough aloft and the mid-level winds shift as it impinges toward the state, as does the steering currents.

Two lows, mainly upper to mid levels shown above with a trough in dashed red connecting them. The yellow lines are showing the leading edge of the moisture 'fiends' ahead of them. Timing if nothing were to change in direction of the leading edge of the moisture fields places them at the beaches by mid-afternoon. However, should the more northern low start to lift more toward the NW and open up, it will be delayed significantly. Stronger storms could be in the 'red zone'
SUNDAY: More complications will very likely abound. So far, guidance is painting a wet picture for all of east central working west during the day along with continually veering winds aloft toward the south from the previous easterly direction of today and early this evening. That means transitions over night and tomorrow abound, with ample moisture. Would not be surprised for some 'bust-casts' unless rain chances for Central and South almost anywhere are put in the forecasts tonight concerning the expectant outcomes of this current pattern. 


With much lighter winds by tomorrow though, would not be surprised that some funnel clouds could not form as showers approach the east coast anytime after 7AM to early afternoon in heavier showers which could continue thunder as well. Tomorrow is a big mess really, and rain chances to not appear will necessarily be restricted from any particular areas of the peninsula as winds continue to veer , especially by early evening. East 'Centrallers' could receive rain more than once from early day activity and then again toward or shortly after dark during the pattern shift.


MONDAY/WEDNESDAY: Steering pattern shift as has been noted now for several posts, with activity taking an eastward rather than westward drift during the day. Although steering will be slow it will be nonetheless toward the east with a weak and possibly slightly delayed east coast sea-breeze. By later Wednesday dry air associated with a TUTT (Tropical Upper-Tropispheric Trough) and Saharan Air Layer easily discernible in specialized satellite imagery approaches from the east. Problems arise in regard to storm coverage during this time frame since it is too far out in time to determine how extensive and deep the dry air will be as well as where and how it will be located across the state Thursday-Saturday. It does not appear so far that all areas will be excluded from receiving rainfall, but it is simply to discern where the dry air will be exactly. Yes, we can go by what models are showing now but it is too soon to say with a high degree of certainty other than it appears the Southern 1/3 of the state will be most affected during the time frame as it stands today. 
"Salty Dusty SAL"


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Thursday, July 12, 2012

Another day for Good Rain Chances Central and North

Threatening Storm Clouds Approaching Cape Canaveral
 from the SSE Tuesday Afternoon
 

TODAY: Persistence in thinking might be the best rule of thumb today despite most model guidance; however, there is a fly in the ointment if the short term Rapid Refresh (formally Rapid Update Cycle model), is hitting on something correctly. As sup-positioned, early rains occurred "somewhere along the east coast south of Daytona Beach" prior to sunrise in the form of a thunderstorm across North Central Brevard County and a bit to the west as it slid ashore, peaking up as the weak wind fields converged along the land/coast.

This radar image was saved at 5:10AM. During the rains (which are lightly falling still as of 7:35AM) dropped over one inch of rain accompanied by in-cloud (IC) lightning.  This area appears to have formed as a result in part due to a weak low pressure area manifesting in the 2000-5000 ft level above ground (AGL)  which showed up nicely in infrared satellite imagery and an accompanying boundary (shown further below). The area appears per satellite animation and supposedly per model guidance (at least) to be moving toward the WNW-W and will continue to do so only slowly the remainder of the day. The NAM might be hyper-reacting to this low by its implication of a much stronger mid-level low forming along the west coast later today. For now, will rest with the GFS which implies a drift toward the WNW but no change in strength. Another low also resides of similar nature off the west coast a good 120NM offshore.  Much of south Florida appears to be blanketed in mainly lower clouds this morning, and whether those clouds will remain or not with such high precipitable water values in place remains a flat out mystery. Most guidance indicates a slow burn off and thus little to no rain in the region south of the Lake today. However, the other opt out is that the moisture going into those clouds begins to lift and transform directly back into more clouds of the rain and thunder producing variety. For now, will opt out on that scenario since mid level winds over the South are forecast to shift from a more westerly direction solution  ..perhaps resulting in only more clouds. Too hard to say.

Two images depict the approaching storm cluster yesterday. Image 1 is clearly from a more distant perspective
 
Today's First Guess, not likely accurate.
Image shows location of the two low pressure areas, both are a bit 'elevated' and weak so far. Thunder central and North interior.


Running with short term guidance and extrapolated analysis data, it appears a good feed of sufficient moisture and instability is poised toward the region off near West Palm and north to Southern Volusia County. With little change in low to mid level winds, would expect a break in activity until temperatures can reach Convective Temperature which would not be until early into mid- afternoon (in support of thunderstorms). South Florida might end up receiving debris clouds from activity off of the SW coast as light west winds take part in the mid-levels (assuming they do).  


Therefore, for this post and without trying to read too much more into an already problematic situation, have left this area out until very late toward or after dark (yellow) for rainfall. Coverage of storms might very well end up mainly near and west of I-95 in the Central region, but given that sea breezes will be weak cannot count out the barriers 'just in case'.  One or two strong storms could occur near the Brooksville area into Lake County it appears, maybe even Osceola, with that region to the north also  in question. Looks more like a standard late day sea breeze collision set up for that region, but if the mid level circulation strengthens...it would be even sooner (if at all) .


FRIDAY-SUNDAY: Although forecast discussions refer to some drying over the weekend, I'm not changing previous thinking, for rebel's sake. East coast could still see isolated activity (especially Friday from JAX to Boyton) sometime between 11am toward 3pm. Guidance has indicated an 'open disturbance ' or trough to wash ashore accompanied by low level convergence and higher PWAT sometime on Friday, but there is big timing differences with the GFS holding off until mid-afternoon. This will make all the difference in the world for the east coast for sure, but more so the west coast. If it holds off until late, the west coast might not see as much rain tomorrow as expected (which as of this hour at a very good chance threshold). Otherwise, continued mostly to partly cloudy skies all regions.


Saturday and Sunday and even into Monday is a very slow transitional process period with little change in thinking. Early east coast and later West Coast rain/storm chances, except Monday is going to have to be 'let's wait and see'. Transitional periods can be accompanied by a periodic dry spell in the pattern shift as parameters and moisture fields get realigned. Better chances of rain many areas appears to be in the cards on Tuesday.
Green Seas and Dark Skies wash ashore in Cape Canaveral Storm

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