The 10-911 " No Name Storm" Of October 9, 2011

"We've been  on the beach in a storm with no name, it felt good to get out in the rain;


In the  storm,  we can't remember the name, but the pressure dropped down and the wind blew insane" 


Events over Florida of October 7-9, 2011, leading up to....

Storm 10-911 (10-9-11) !

 Some of the events that led up to the final escapade that prompts the question, "Should this storm have been named?" when all was said and done.


The initial weather pattern  leading up to the time in question was expected to be a wind/rain event as first noted by the Melbourne, Florida National Weather Service extended forecaster on Duty, Mr. T. Cristaldi (and followed up later the same morning here) was not a tropical or even sub-tropical one. 


As noted, a blocking pattern was to set up with high pressure over the Mid-Atlantic that was to be reinforced from a secondary high pressure area from Canada.  Meanwhile, low pressure was mounting in areal coverage from the Florida Straits and into the Caribbean along and south of the old cold front that brought the state the first hint of fall on October 1st.


It was posted here originally that I thought it looked like an OMEGA BLOCK was going to set up, but that quickly changed to resemble a REX BLOCK as noted by the NWS office. Technically,I'm not sure either case was absolutely true because for these blocks to form in 'text book fashion' both areas would be cut off from the main Northern Hemispheric circulation. It was quite close though, and even that could be up for debate.


In this case, the low pressure area was far enough south to not be part of the circulation, whereas the high pressure had nearly cut off with a large trough well to the east . Recall there was also a trough approaching from the west that nearly cut off in the upper levels toward the SW U.S. That would have made for an Omega Block. So, and only from the perspective of this writing for entertainment purposes, I'm thinking of it as a "Modified OMEGA/REX Block". This term does not exist to my knowledge technically  ..but it harbored both aspects of an Omega and a REX Block, but not completely.


It was within this block  that Florida found itself within a tightening pressure gradient portion of it that brought the high winds. On the other-hand, the weather over the Great Lakes and most of the NE states was gorgeous where it had been previously wet and cool for a long duration when a cut off Low had established in this area just 10 days earlier. In fact, it was not until that cut off low (a blocking pattern as well), moved well off the U.S. NE Coast that the newer pattern could establish over the SE States.  


 The deepening easterly flow from the surface to 700mb was discussed in depth early on, and was described in posts as "Phases I, II, and III) early in the week to midweek as they unfolded ..it was when the flow became deep enough (or higher up in the atmosphere) that heavier rains and squalls began in full, Phase III.


Despite all this wind and rain, it was not a case for 'naming' the events that were on going. Not until there is a closed low pressure area at the surface does the 'naming' come into consideration.


Such a low appeared to take shape toward the NW Bahamas on the evening of the 8th. The old frontal boundary (cold front of one week earlier) lifted north, pivoting from the west side and lifting north on the east side.  As the boundary lifted north the pressure gradient (between high and low pressure) increased across Central Florida leading to the events of Sunday, as anyone who was in  Florida can relate too. Unusually high tides, minor beach erosion, rising waters and waves on the intracoastal waterways, and squally weather continued. Along 528 between Cocoa Beach and Merritt Island it can still be seen where the river breached the banks and flooded over where no barricades had been previously put in place. Water is still over the banks in a few spots where the shore was eroded on this Wednesday, October 12, 2011.    


OCTOBER 9 - The Day in Question: It was on this day toward early afternoon that a tightly confined and consistent cluster of strong thunderstorms moved north to NW off the Florida East Coast which developed offshore Vero Beach. Winds in this location increased in that area, and power outages began to filter in. It lofted NW- WNW to almost West toward Brevard County. The NWS in Melbourne issued high wind and Flood warnings especially for that point in time, and had been issuing lower key statements prior to the warnings in their Blog updates. TV news stations were put on alert and the NOAA Weather Radio was emitting the warnings as well.

It first appeared it would impact areas as far south as almost Ft. Pierce to north of Brevard, but as time went on the area of interest shown above lifted further north and parallel to the coast inching only closer westward with time as it reduced in size. The blue lines were drawn in at the time in order to point out that it was a coastal event, per the rain at the coast that was creeping west with time.


However , the area offshore lifted north more and more,  then started to take a hard left (toward the west)

At this point, I was listening to Led Zeppelin's Song, "When The Levee Breaks"

It started taking on more striking features on radar during this time, almost like banding around a tropical storm, but there was no center of circulation visible on radar or satellite imagery. It also increased in strength for a 'blob' with almost no lightning to abudant lightning after 4pm  -9pm. The HRRR model was showing what looked like a  "SuperCell Thunderstorm" at one point to cross exactly where the 'center of circulation' eventually crossed many hours later. That was about the 15Z run of that model, but cannot say for certain. It becomes available on line several hours after the fact.  At this point, the system was being more regarded as a potential low end tornado threat rather than a tropical one, as SPC also had this area under a "See Text" for a 2% Tornado Risk and strong wind risk . A second blog post was issued on this day as the new and evolving events began to unfold. Both the early and mid-afternoon posts are available (the image (below) included in the later post):


 http://highspeeddirt-steve.blogspot.com/2011_10_09_archive.html

The Green Area Shows Where the Storm Prediction Center (SPC) based in Norman, Oklahoma had issued the small tornado and wind threat. In blue was the modified version, unofficial for purposes of the blog posts, posted in the morning of the 9th. The SPC version was published earlier in the day, whereas the blog post was not issued until several hours later when the sun had been up a while and conditions to the south were improving conditions  

It was near 11pm the lightning activity began to cease..as the remaining convection moved ashore on the north end of Port Canaveral, toward the Kennedy Space Center, to along SR 3 in North Brevard near the Haulover Canal. At this point the boundary I've referred to as a warm front (not completely technically correct) was near or just south of Melbourne , Florida...and the pressure gradient was very tight along a narrow passage just north of that boundary where it met the strong high pressure to the north. But.....

The lightning ceased, and surface air temperature around Cape Canaveral at my place fell to nearly 68F degrees, almost the coolest it had been since early spring  and one degree shy of the coolest morning yet this fall season. Then after approximately 10 minutes of uneventful weather,  an interesting thing occurred in Cape Canaveral as I observed. The wind began to pick up again, from almost due north this time. I big change from the ENE-NE wind of the past two days. It seemed like more a fluke, perhaps outflow from the remaining storms to the north (?), but it increased steadily. A closer look at radar, and an interesting feature became visible within radar range of MLB's WSR-88D Doppler Radar.

An "eye like feature"  to the ENE of Melbourne clearly was showing what looked like counterclockwise circulation as if around a central core of low pressure when viewed in animation mode (using weathertap.com) similar to that of a tropical cyclone's eye.  If there was a circulation , just like the HRRR model implied for a supercell (a rotating thunderstorm,) it was now just offshore but not as  a rotating thunderstorm.  Realize the supercell thunderstorms do not have an 'eye', the entire storm rotates.


Something else was apparently rotating as it lifted NW then turned WNW and into North Cocoa Beach toward Cape Canaveral. A look at the Radial Velocity revealed:

The strongest inbound winds are shown in the darkest blue just off the tip of the Cape and heading toward the north end of Port Canaveral. The red is outbound winds relative to the radar's location.

 Rhe air pressure on my home weather station (but who knows how well it can be trusted) indicating a RAPID fall in pressure from 29.82" to 29.70" in less than an hour.


Also note the 00Z Forecast from the North American Model (NAM) for this time frame for 2AM. It is 'slow', but does show the closed low roughly east of Sebastian Inlet:

Actual data that appeared from the Local Data Integration System (LDIS), a conglomerate Space Flight Group/NWS effort. Compare the image above and below, and note they both picked up a 'low', but it does not look like a Tropical Storm at all. But, it is a low, with tropical storm force winds on the north side.

As this apparent circulation approached the temperature rose from 68-69F to 74-75F degrees on my porch , even while it was raining. This should have been a cold, outflow like wind from storms to the north, but it was not. It was warm wind. 


Wind shifted in MLB to westerly while my location in Cape Canaveral just south of the Port had due North Winds estimated at 35G67mph (tops) in one quick squall. The prevailing mode was more closer to an estimated  30G48mph at my location...which lasted 50 minutes.  Rainfall of 2.67" was received in only 50 minutes and the storm total was 2.75" for the 90 minute period, although with how strong the wind was at this time I can't be certain that total rainfall was not even more. Rain was over-flowing the rain eaves above, which I've only witnessed on 3 previous events in 5 years. Radar estimated rainfall did not catch the high rainfall in Canaveral from what I could see on Weathertap at all, and I'm not sure if Melbourne's radar picked it up either. It is possible it was below the radar beam, since it all appeared to be very low level activity for the majority of the time. In fact, at times we could see the Full Harvest Moon in brief cloud breaks.

On Shore Centered Close to Port Canaveral shortly after midnight

And the latest LDIS Plot at the same time as this radar image above is below. Note how tight the isobars are shown here AROUND THE CENTER, and not depicted as a tight pressure gradient between two opposing much larger non-tropical systems. It was during this time the weather station outside registered a barometric pressure of 29.47".

It is only for this odd mesoscale feature that I'd think the system would have a potential to be named.54ft towers near the north end of the Cape measured a few gusts from 75-81mph as well.


It is important to note that most of the strongest winds worthy of rating this as a named storm occurred only in gusts, but might have been sustained toward the Port and further north toward the Haulover Canal or off the east coast. A cruise ship leaving harbor (I saw it going out to sea later in the afternoon as the system was approaching) relayed they encountered 'great difficulty', more so than expected.


Despite these winds measured on land, we'll never know how strong the winds were offshore as well due to lack of denser buoy data. The items of interest in my mind that would give this final 'obscurity of meteorology' the potential to be name worthy are:


 1) The rapid drop in surface pressure (not related to pressure gradient winds) 


2) The abatement of lightning as the system could have become warm core to higher altitudes which is not favorable for lightning activity, but denotes a tropical system;


 3) The rise in temperature at ground level despite the fact the wind was coming from the north in my location, and from the direction that cooling outflow from earlier thunderstorms would have come from ;


4) Even as the moon appeared in full, the wind continued sustained est'd around 30mph with gusts to 45mph with horizontal rain.


5) It might be that the strongest measured winds at 54 ft were a result of both a tight, low level circulation and pressure gradient winds combined.


If this were to be named, perhaps it would be the first "hybrid sub-tropical storm gone near extra-tropical"  all within the course of 4-6 hours.  

From the perspective of a Storm not to be forgotten in the annuls of meteorological research and history, perhaps it should be named for historical purposes. Would naming the storm affect those looking for recovery from insurance companies (for better or worse)? 


Names are not dealt out solely  for the purpose but other factors both pro and con abound for why or why not it could be named.  Post-event naming has occurred in the past.


The series of bizarre events leading up to the night of '10-911!' are not truly defined well enough to argue either way, nor is the availability of data surrounding the system during this time in-depth enough. It is within the hands of our scientists at the National Hurricane Center in collaboration with NWS Employees to decide (if they are even giving this storm event a second look).

Will we, the witnesses, be forgotten like salt spray in the wind once the storm's flood waters absorb back into the ground and vaporize into the air as the beaches recover?    


For a personal video now posted on YouTube, See:   

http://www.youtube.com/watch?v=uZX74NxHBZw


 Meteorologist, Stu Ostro, from The Weather Channel, has   posted a discussion regarding this event (link below):


http://www.weather.com/blog/weather/8_25746.html


Crown Weather Services, Rob Lightbown, was also concerned about the potential for an event to unfold, and his daily weather update for this day reflected that fact early in the morning. His feature/main page is located below, and is updated most every morning as tropical weather season is in progress, as need be: 

http://www.crownweather.com/

The National Weather Service out of Melbourne issued prompt and due warnings, in any event. So there is no argument either way that people were not warned for tropical storm like conditions in the areas that were impacted on this day.


And Thanks to Weathertap.com, whose services have been always necessary and reliable
and to Twisterdata.com, where the weather model data provided at this site proves beneficial innumerable times .


STORM: 10-911

Similar To Tuesday, With Showers and Isolated Thunder Near the East Coast Late Afternoon

Weak Trough that was over the Eastern Gulf Yesterday crossing South Central Florida early Afternoon accompanied by some brief showers. The trough is washing out, with another one off the west coast to replace the previous one.
More showers along the second trough toward North Florida currently. 

IN GENERAL : The mid-level low that was just east of Panama City is lifting north toward the Great Lakes and being absorbed into a larger upper level trough moving across the Northern Plains heading into Friday. The weak surface reflection is riding up the eastern sea board and toward the New England Coast through Saturday and will also be absorbed by the larger system. This will all occur during the next 3 days over the Great Lakes region, with portions of the Eastern Sea board receiving some heavier rain and thunderstorms. This large low pressure area will be slow to move out, as it now appears the primary frontal boundary might occlude.  


For Florida, the weak trough that was off the West Coast is sliding through Central and South Central Florida at noon, and setting off some rain showers along the way. It appears it is weakening with time and might fizzle altogether by late afternoon. Another similar trough seems to be more associated with the mid-level low, and that is to move toward the peninsula slowly today. Not sure if it will even play in though with weather over Florida locally.


There is moderate instability showing up now on the LDIS plots in the Eastern Gulf  from near Brooksville north of Tampa Bay toward Ft Myers. This is expected to wash across the state through afternoon and reach the east coast a bit stabilized by that point in time due to lower sun angle and no outstanding other parameters at play under a zero convectively inhibited atmosphere south of the Beach Line.  Thus, much of the instability will escape freely into the atmosphere, but what remains appears will be limited to Central Brevard and South to Miami..with a secondary area closer to the secondary trough approaching Eastern North Florida toward Ormond Beach.


A light East Coast Sea breeze has developed and expect it to not get much further west than I-95 today. Otherwise, much is similar to yesterday. Cirrus clouds moved in as expected, but are not nearly as dense as feared they would be, thus the sun is shining about 50/50 across the state.  Some thunderstorms possible near and east of I-95 late afternoon through mid-evening, possibly or mostly occurring just offshore.


THURSDAY: A pre-cold frontal trough will cross the state tomorrow, with another chance of conditions similar to today, although activity might be more showers and starting earlier in the day and maintaining through dark. There might not be a sea breeze tomorrow, and if so, it will remain within 5 miles of the coast.  Much still needs to be determined for tomorrow concerning cloud and shower coverage. If showers hold off until at least mid-afternoon and sunshine can work in, thunder storms could become a bigger reality, but at this point it looks like 'shower mode '.


FRIDAY: The actual cold front , at last, gets here. This is the same front that was generating snow over the Rockies before the Big Rain event even started over Florida. Recall, we were in a Blocking Pattern that prevented the front from continuing to the eastern sea board for several days beyond the norm. The front will cross Central around mid-morning and reach South Florida after or near Sunset. There is not much if any activity associated with it as it seems, primarily because as of the 12z GFS run, it appears that jet stream cirrus might be streaming out ahead of it from the Yucatan region. The front will get about as far south as the previous front, the Florida straits.


SATURDAY/SUNDAY: Not much cold air with this front, with morning lows briefly in the mid-50s inland and remaining in the low 70Fs closer to the coast. Afternoon highs in the low-mid 80Fs (about 2-3 degrees cooler than the past 2 days) is about it. The front will begin to work back north to Central Florida by late Monday, and as such does the rain chance .  Weekend looks worse over all for the Keys and perhaps far south Florida.


MONDAY- EARLY WEDNESDAY:   It appears they front will retrograde  back to Southern Volusia sunrise to sunset of Monday, with rain chances beginning most anywhere south of Volusia County by mid afternoon through dark. The boundary continues north and the remainder of the state gets in on the rain chances heading into Tuesday. 


These days look like a 'mini-event' of what happened the last few days ago, but will behave not at all like it. Not as much wind, but still plenty of rain fall. Flooding might become an issue in those areas that already received too much previously which is pretty much everywhere except a few locations that lucked out with that last event. The bigger problem with the rain will be for those areas that drain poorly and are still water logged. Not looking at big rainfall totals, SO FAR..at least, not as high as the EPIC totals of the previous event. But nonetheless..2" or more is not entirely out of the question, especially near the coast .


THURSDAY: The 36-48 hour event will end with another cold frontal passage. This second front, as noted previously, could become KEY to what the weather over and near Florida will be like by next weekend. The GFS has varied on the southern extent of the boundary, varying from over Cuba to stalling over Central Florida. In turn, that also affects where any possible tropical activity can form in the SouthWest Gulf, across the Yucatan, and into the Caribbean Sea mainly well south and west of Cuba. Simply too soon to say if there will be another Tropical Storm to form, but the GFS is implying it now with every model run (every 6 hours), but varies vastly on where it will form, how strong it will be, and where it will go..anywhere from SW Texas to Off the Florida East Coast. That is a Big IF.

Scattered Showers, Isolated Thunder Mainly Central and North

Image from the NWS, Melbourne. Link shown in lower left of image. This plot is the 1km helicity and low level winds, which was used because it shows
in the most simple terms today's scenario at the surface. A weak surface low is near Panama City, whereas  a mid level low is much further north. A weak surface trough extends just off the Florida West Coast, as another across the Panhandle to just west of Jacksonville. Colors are explained further down in the post. 

As shown above, there is a surface low near Panama City ( I did not draw it in but it can be seen by following the direction the wind barbs are pointing) , and a mid-level low further north. This can be seen by the infrared satellite image below. The mid level low is expected to lift N-NNE to the Great Lakes while the low level surface reflection rotates around it to the ENE-NE toward coastal South Carolina in the next 24-48 hours.
The surface reflection should ride up the eastern Sea board while the mid-level reflection lifts toward the Great lakes region by Friday. In the image above:


1. Green, mainly showers
2. Yellow, Chance of  Very Isolated Thunder before 6pm
3. Orange, Chance of  isolated thunder until 8pm
4. Best chance of there being thunder, Red


Using a blend of the RUC and 2AM GFS, it appears the showers moving into SW Florida and north are a result of cooler upper level temperatures and higher PWAT (precipitable water) air, but thermal instability is greatly limited due to poor lapse rates and lack of heating at this time of day. It is not expected we will warm up all that much today, and the sun angle is getting lower (have you noticed lately?). 


 The best chance of thunder will be right at peak heating toward 9pm. CAPE (convective available potential energy) is not looking to get much above 1500 Js/kgs which supports the weaker low level lapse rate theory, which is barely considered moderate instability. Most of the instability today will be in the mid-levels.


 Lack of deeper moisture and more unidirectional winds further weakens the thunder chances. The best chance of thunder will be along the east coast sea breeze boundary which will be stuck close to the coast toward I-95 and East , developing after 2pm (earlier SE Florida).  Drier air is trying to move into South Florida, but showers and who knows, maybe a thunder could occur near the same location as where some occurred late yesterday (near West Palm Beach). (That area will be   more favored  Wed/Thursday)

INFRARED FROM 8:45 AM EST. The low level low pressure area in the Panhandle is barely discernible in this image, being composed of only low clouds in this infrared image which uses cloud top temperatures to provide a picture of what is going on. The white and brighter the cloud tops, the colder (and higher) the clouds. You can barely see the clouds over the Panhandle of Florida because they are 'warm' by comparison to those north and out over the Atlantic . The large mid-upper level low is more easily seen because it is composed of colder clouds (tops), which the satellite can detect (N. Georgia). There is a pseudo warm and cold front couplet
extending from the surface reflection as noted by the dotted white lines, per the wind fields. The blue lines point toward where most of the moisture will be heading today to support more showers and possibly isolated thunderstorms during and after peak heating toward mid-evening.

This is VISIBLE satellite imagery taken just as the sun had risen enough to reflect off of the cloud tops. Note the dense combination of clouds in the low through upper levels over Georgia. By Pensacola toward Panama City most of these clouds are only low level clouds as noted in the previous image. Showers can be seen moving from the Gulf toward Sarasota with stronger showers just to the north along the dashed , white 'cold front' portion of this system. 

MORE ON TODAY: The surface reflection low will move toward the NE-ENE today. Best chance of thunder will be along the weak trough axis toward NE Florida as far south as interior Volusia County, with a secondary area further south where it could become more unstable toward Central Brevard county and toward the interior, but mainly along to just west of I-95 and eastward.


WEDNESDAY/THURSDAY: The tag team of lows will lift north, with the surface low shifting toward off the SE U.S coast while the main feature low lifts north to the Great Lakes in response to a another system moving into the Pacific NW. This ensemble will be a trouble maker through most of the weekend in the NE States, with a severe weather threat possible in association with the surface reflection near the East Coast states as it lifts north.


Otherwise, the trough associated with the surface low shown by the dotted white line will cross Florida on Wednesday as thought yesterday. However, jet stream level winds will be the driving factor to scoot it along, and with those winds models are indicating a plume of upper level moisture, which would mean abundant 'cirrus clouds' . Those clouds stabilize the atmosphere because they prevent the sun from shining fully. Otherwise, this could have been a good day for stronger thunderstorms considering the wind fields.


Wednesday could end up being cloudy for most of the state due to high cirrus clouds with less clouds to none in the lower levels. The area from South Lake Okeechobee to Miami might escape the worst of it, so a storm/more likely a shower could form toward Palm Beach or Broward Counties. This will have to be all re-evaluated tomorrow morning.


WEEKEND: Cold front to pass through early Friday followed quickly by NNE-NE winds at the surface and West winds just above the deck. The surface front should be forced south toward the Florida  straits if not to Cuba.


Behind the front, morning lows from Orlando and West and interior Osceola County could get into the mid-upper 50s, but the beaches will remain in the 70Fs, with afternoon highs in the low to mid-80Fs inland both days.


BEYOND: Winds will remain from the ENE-E for much of early next week with some stratocumulus clouds working in and spreading across the state during the late morning through early evening hours. Some sprinkles are possible, esp. toward South Florida, but no big deal. Another cold front will quickly move in mid-week with a rapid wind shift toward the South and a chance of Thunderstorms around Wednesday or Thursday.


WEDNESDAY/THURSDAY and 'THE GREAT BEYOND': It gets very sticky from here on out. Next weekend is not looking so great at this time for outside activities of full day duration. The SECOND front, has as been advertised now by the GFS for several runs, is the beginning of what could be something 'big', in regard to weather / rain producing capabilities.


This front could stretch out well, well, WELL east into the Atlantic along an even latitude and remain nearly stationary across the peninsula as it gets squeezed in behind high pressure behind the previous front that will go through on Friday. The subtropical southern branch jet could lift out as well, leading to little progress of any low level features as low pressure in the Caribbean toward the extreme SW Gulf is 'triggered' along the prior frontal boundary  of this weekend.


It becomes quite complex from this point on. Reliability in terms of 'something' evolving in the Southern Gulf toward all of The Caribbean is looking more certain at this point, since this is not all so far out in time, but it remains sketchy and varies from run to model run on just exactly how, where, and why things will evolve.


The trend has been to focus the attention more toward the SW Gulf and the Yucatan rather than Jamaica. For example only, the GFS is now tracking a large tropical storm from the SW tip of Cuba that forms in the BOY (Bay of Yucatan) to Ft Myers, crossing near Melbourne, FL and then lifting into coastal South Carolina as we enter the last week of October (around the 22-24th time frame). This scenario will change in   a vast array of parameters in each and every model run of the GFS as well as other models.


Point is, the period from October 19th -27th could be turbulent either over Florida and/or the Carribean and Gulf of Mexico with a tropical threat anywhere east of the Mississippi River. Watch the BOY.

The "Storm With No Name":Scattered Showers, Isolated Thunder Mainly East Side Late

What looks like an "EYE" can be seen in this radar image from WeatherTap last
night east of Patrick AFB. This feature moved WNW-W and came ashore near the 520 CSWY in Cocoa Beach. Animation of this feature was impressive as it became visible on Melbourne's Radar when considering it wasn't supposed to exist. 

ANOTHER IMAGE: Below. This is from Melbourne's Local Data Integration System (LDIS) available from their website. Shown is lines of constant barometric pressure. Note the tiny bulls-eye along the south end of Cape Canaveral. The strongest winds last night occurred north of this feature, from the north half of Cape Canaveral to the Brevard/Volusia County line. Wind gusts measured at 54Ft above ground contained several gusts between 75-81mph, and land based observations recorded winds over 50mph from near Vero Beach north. A separate post concerning the event and of days past (the weekend) should be in the works later today or tonight.. A brief YouTube video is also in the works.


Note the tiny bulls-eye just south or on the 520 Cswy in Cocoa Beach in this image from 11:45pm last night. Winds in Canaveral at my location had gone from estimated gusts near 65-70mph to only 6 mph in a matter of 15 minutes. Barometric pressure fell rapidly, and bottomed out at 29.47" (from 29.88" three hours earlier) per my weather station.


 Meanwhile, Melbourne which was south of the feature was reporting a west wind gusting over 20 mph.

    

In regard to last nights system, it had been outlooked by the Hurricane Center as an Invest, but I think that the ball might have been dropped on not naming the prime area a Tropical Storm and fairly high end one at that. Several problems with doing so though, other than for the sake of 'naming a system' (which in the past they've seemed to have no problems with doing so in much more questionable situations out in the middle of the Atlantic) . This might have been all coordinated behind the scenes, but I'm not getting that impression.


 It is a good thing the NWS Melbourne had issued high wind and flood warnings  in the afternoon, although those were issued for a different reason other than what eventually developed.  There is some procedural politics involved.


 The saving grace was that the highest wind and rain impacts occurred in a very lowly populated area of the Mosquito Lagoon ..with the only inhabited areas fully affected being the north end of Cape Canaveral, possibly some areas near SR3 in North Merritt Island as well. Hurricane Force gusts were measured at 54 Ft, and tropical storm force gusts were measured in a bigger area.  Further reasoning for why it could have been named is it seemed to go 'warm core' as it approached land, as surface temperatures ROSE even during heavy rain and lightning ceased (indicating warmer air aloft as well).
Radar animation overall was the most one single 'red flag' though.


TODAY: The low pressure system "that wasn't" (?) has exited the Big Bend area. A tornado watch had been issued for NE Florida, but none have been reported and it was dropped for that area. The low is wrapping into the parent mid-upper level low over the Eastern Gulf. Otherwise, models agree fairly closely on these features.


The morning surface plot:

The low circulation is now barely discernible, but appeared to be just west of Gainesville. The main feature low with upper level support is west of SW Florida extending toward Jacksonville. The red arrow on the east coast indicates the prevailing wind direction later today.
 

In the Mid-Levels of the Atmosphere, per LDIS:

There are two circulations noted by the red "L"s. Moisture remains, but there is some drying in far South Florida. Otherwise, steering early was from the SSW, and fairly fast at 20kts. This should decrease only slightly later today.

TODAY: The NAM has been consistent for three consecutive runs with showing scattered showers forming toward SW Florida and spreading East and north with time. Most of this activity should remain showers, with maybe some thunder toward Osceola County. 


Winds today are expected to become 'side-shore' except toward West Palm Beach due to the configuration of the coast, and along Brevard's Barrier Islands. The atmosphere will take a while to destabilize, but South Florida is getting underway right now. The two source regions for instability today will be South Florida and the near shore waters of the Atlantic. Instability should advect up the coast and  rivers during the day, with  possibly a sea breeze creating a storm, possibly strong, toward West Palm Beach along what could be a Lake Okeechobee/Sea Breeze merger variant. This should occur toward mid afternoon.

Further North, a slight sea breeze could develop, but expect winds will remain SSE nearly parallel to the shore except over the Barrier Islands of Brevard County. Instability from South Florida as well as the Atlantic Waters could arise to showers progressing from the west and southwest along an upper level trough feature rotating around the mid-level low configuration pictured above off the West Coast. As this area approaches the East coast the showers will encounter a full days worth of mounting instability and side shore winds with steering from the SW. It is possible that in this area, especially in North Brevard, that a strong storm could form during the last hour or two of daylight and move offshore . More rain showers and maybe thunder could occur further north into Volusia and Flagler, but showers so far seem to be the rule in those most northern locations. Temperatures aloft are still very cool by the summer standards of the past wet season, with 700mb and 500mb temperatures running around  +7C / -7C respectively, and perhaps a degree colder with one or the other of those. Thus, if any much stronger storm than expected occurs, tiny hail is possible, but I do not believe at time that upward forcing will be strong enough for this to occur today. Any stronger storm could have gusts to 50mph, but given the events of the past two days..it won't seem like much. The other complication for thunderstorms, especially a stronger one, is that the days are getting shorter...and heating is decreasing for less instability. So nothing is a given today. I simply do not trust this low pressure system out in the Gulf. Its presence puts a twist on things.

Showers in Green, maybe some thunder in orange, with thunder more likely toward the coast along and east of I95 .
Some showers in North/Central Brevard to Volusia, with thunder waning, could last until 10pm or so.

TUESDAY/WEDNESDAY: Overall atmospheric moisture will be waning as the upper level low starts to open up and lift north up the east coast. It will be a slow process though, and timing of the required features becomes increasingly difficult as well as key to determining where/when and 'if' thunder will occur . It does look at time that Tuesday will be similar to today, with a slight variation due to decreasing moisture and possibly later sea breeze development. Temperatures aloft will be warming somewhat on these days, but not so much as to completely negate the thunderstorm chance.  


Eventually, as we head toward Later Wednesday, the low pressure party will lift up the east coast, with an attendant surface trough dragging behind and across the state. This could be key to some stronger storms again on Wednesday mainly along and south of the Beachline toward the Eastern Interior of South Florida.

THURSDAY: Big problem. The NAM is consistent with developing a low pressure system along the northern banks of Cuba and lifting it northward to 70-80 miles SE of Key Largo, Florida. So far, at best this could be dubbed a tropical depression...but winds do not indicate it will be strong enough. It does look fully tropical though, with no jet stream winds near by and warmer air aloft. Chances are, this would be regarded as another "Invest".


If this system does develop, the forecast for Thursday becomes a problem in regard to rainfall. So far, rain chances look very low, although any sliver of moisture that is broad enough could generate showers and maybe a thunderstorm across South Florida and Central, but very isolated if even.


BEYOND: Cold front is having a big problem getting  through the Southeast States and Florida, but the GFS remains adamant that it will plow through by Friday, late...as the low supporting the frontal boundary weds with the low pressure  system/systems from the Southeast states. Another low may form and move up the east coast just offshore during mid-week from the Mid-Atlantic toward New England.


Temperatures will not get quite as cool once the front moves through, and onshore winds resume much more quickly as well. This front could pose as an impetus along with a disturbance from the SW Atlantic for tropical develop again later next week near the Yucatan, or even the west central Gulf of Mexico. 

Watching Weather Conditions For This Afternoon Central/North Central Florida

 

 

 

There is a large 'blob' of convection off the East Coast of South Central Florida at noon. It appears to be located/resultant from upper level divergence and low level convergence at the negative tilted base of the 200mb (40,000 ft) jet stream flow. Other convection along the SW Coast of Florida seems to be associated with a 500mb low within this trough.

 

There lies the 'potential' for the branch flow in yellow to weaken and/or cut off, at which point convection along the Florida east coast could stream inland. Mainly after 2pm. The latest 18 hour RUC simulated radar animation is showing showers with embedded thunder to stream in mainly near the north end of the CAPE, well inland to the west coast from that point as the flow around the low off the SW coast takes over the steering currents.

 

The latest HRRR model (which runs several hours slow unfortunately) is bringing 'some' activity on shore, to lesser extent, but stronger from Indian River County and north, with ONE strong storm moving across Central to North Central Brevard late in the afternoon.

 

Thus, although little to no rain is occurring at this time..or is mostly moving out, this could be because the low off the SW coast is wrapping up (closing).

Heating is occurring in cloud breaks for the time being, but some high clouds are working toward the East coast near Brevard.

 

Latest water vapor animated loops show much of the state is being 'dry slotted', however, SPC Mesoscale analysis shows that there is ample moisture in the convective layers between the Lifted condensation level and the level of free convection.  A pseudo warm front is moving slowly up the state from far south Florida at noon, and winds at the surface are responding to the tightening pressure gradient...as well as backing a bit more toward the NE in Northern Brevard (for example). Winds aloft below that level are more from the East to ESE.

 

Any severe weather to occur will likely happen in a very restricted area (if it does at all) right ahead to right behind the surface boundary.

 

This is just a 'precautionary' post. The situation would be much more clear if we were dealing with a strictly tropical or strictly non-tropical situation, but this one is neither. Models did not handle the precipitation fields well in regard to where the heaviest rains would occur for this event, but did handle the latitude at which they would. Osceola County likely owns the highest rainfall totals. For this reason, even today's events if they occur at all are highly questionable.

 

Another area to watch is interior SW Florida.

 

 

 

Windy With A Small Chance of Severe Category Storms By Noon

Current conditions as of 5AM. The trough still appears to be more of a 'warm front'. The image annotations are described below in the over view / explanation portion.  Note how TIGHT the isobars are compared to previous days.

TODAY: Very windy, mainly at the beaches through noon, but spreading well inland by noon. Winds should increase with sunrise and spread west toward the interior, especially north of Lake Okeechobee to the Beachline by mid afternoon. Generally, winds within one block of the beach and along the west banks of the Banana and Indian Rivers in exposed areas will be in the 24mph range with gusts toward 40 -42mph. ALTHOUGH, I saw an observation last night out of Virginia Key east of Miami reporting gusts to 52mph. Something to be advised of. This was likely related to heavy rainstorm activity in the area.


As I type, I can actually see stars?! While showers are inland and some strong rainstorms  are further south not far away.


Very little change in the line of thinking from yesterday's post. This post includes agreement with comments relayed by the National Weather Service Offices in MIA and MLB, which surprisingly were what was written here yesterday. They also are in line with those from the Storm Prediction Center (SPC) based in Norman, Oklahoma, which also match yesterday. Those being:


1) The SPC refers to the boundary near South Florida as a 'warm front'. This boundary will lift north from its eastern flank while moving little on the western flank which is embedded more toward a supporting upper level trough. Thus, this boundary will 'pivot' from the western flank while the eastern side will lift north and west during the day. As it does so, the pressure gradient between high pressure to the north and low pressure associated with the boundary will increase, thus the high wind threat. This will occur during the late morning through sunset.  In doing so, helicity along the northern lead of the boundary will increase, but mainly in the levels of the atmosphere above 2000 ft to 12,000 ft, whereas at ground level winds will be quite unidirectional (from the same direction). However, with any minor ripple or glitch in the current line of thinking there could be a threat of an isolated tornado. 


The purple area in the image above is where it appears that threat will exist between 2pm - 7:30pm, although it could be earlier than this for the region along the south end of the outlined area. 


The second reason to downplay a tornado threat as noted yesterday is that thermodynamics (instability/buoyancy) will be lacking due to lack of heating with cloud cover that is expected. The biggest threat areas though should be within 20 miles of the coast (east coast) where any long lasting and better breaks in clouds might occur. More appropriately, up to 10 miles DOWNSTREAM of where those breaks occur.  Any storm that might contain thunder should be a red flag today, but that too is questionable (thunder).

This is SPCs thinking  , as noted :  EXPECT NUMEROUS SHOWERS WITH 
WIDELY SCATTERED TO SCATTERED/EMBEDDED TSTMS IN 
CLUSTERS NEAR AND N OF WARM FRONT. BUOYANCY SHOULD 
DECREASE NORTH OF WARM FRONT WHILE LOW-LEVEL SHEAR/
SRH (Storm Relative Helicity) INCREASES.


This is their threat area in the image below. I threw in my own 'slant' for a 'threat area' 
of possible tornadoes as well in blue, but realize the SPC outlook is official.


Outside of the conditional tornado threat, any storm today with thunder could be severe thunderstorm warned if conditions warrant for 'winds' in excess of 58mph, since this
activity would not be related to fully tropical activity. This very well may be the case, 
but again, the question becomes, "can we even get thunderstorms in here today with 
warmer air aloft/less instability? The GFS implies there will be some instability, whereas the RUC which has been doing plain awful since yesterday, says 'no'.

THE OFFICIAL SPC OUTLOOK From Early Morning is in Green. This might be removed by 8AM though, but I doubt it. One can never be too careful in these instances.

2) The NWS Melbourne is also mentioning this threat in their early morning discussion, 
possibly because SPC had. They have mentioned it in the past though, but for a different reason.This treat looked real enough yesterday for the reasons cited this morning though for it to be mentioned in yesterday's post.


OTHERWISE:
SOUTH FLORIDA: Winds here from Palm Beach and South will decrease significantly 
with the passage of the warm front 'like' boundary. It appears this should occur by noon 
time. In fact, it will not be windy at all once it clears. Rain chances also diminish greatly, but some stray showers or even a thunderstorm 'might' occur. Temperatures aloft have 
warmed as noted yesterday , hence the lack of thunderstorms this morning and the other reason why the tornado threat is conditional.


CENTRAL FLORIDA: Front pivots from the western flank, with the eastern flank lifting 
north and west. Pressure gradient increases further across South Central/Central Florida. Rain showers and possibly thunder could form/increase after sunrise, although some areas might not see rain at all until at least noon if ever.


Pressure gradient. At this time, the barometric pressure near Tallahassee is 30.10". In Ft Lauderdale it is 29.80". The gradient is the degree of difference between those to 
numbers. On a normal summer day, they run close to identical. 




The warm front is expected to lift north of the Beachline around sunset or shortly
thereafter, at which point winds quickly wane , followed by waning rain chances as well


Further north, rain chances toward the east coast from Volusia County and north could 
continue past midnight but end by sunrise.


MONDAY: During the day , the boundary will have swept into the Gulf and become 
aligned NE to SW in the Gulf close to the upper level low. A weak but broad surface low will form from the mid-levels down to the surface of non-tropical nature, although this is debatable. Another low could exist near the Florida Panhandle along I-10 east of 
Tallahassee. Monday will be quite pleasant with standard fare land breezes in the morning with a South to SSE wind nearly paralleling the coast in the afternoon. Some 
thunderstorms could form under the conditions, but rainfall should not add up since storms will move from the SW at 15-20mph. Most likely, late in the afternoon , and could last 
until after dark, around 9pm.


TUESDAY/WEDNESDAY: Similar to Monday in the wind department as the low in the Gulf lifts NNE toward the Big Bend. This low will have a surface trough with it, a bit like a 
'pseudo cold front'. My line of thinking now is that thunder will be more likely Tuesday 
with this boundary and moisture still at play. On one or both days some of these storms 
could be strong along and east of I-95. The low will lift north through Georgia and along 
or just east of the Appalachians, with a secondary low running up the eastern sea board 
eventually toward the Statue of Liberty/New York early in the week.


THURSDAY: Remember , there is still our cold front from the Rockies that created
the early season snow. It is expected to be preceded by a prefrontal trough on Thursday with the front to follow sometime Friday. As of the last run of the GFS, that would be 
near noon on Friday. Rain shower/storm activity is expected to be quite low, or at least 
limited in strength and expected to be isolated showers mainly. The front should clear 
the state by Saturday morning and enter well south into the Caribbean during that day...making for a very pleasant weekend.


TEMPERATURES WITH FRONT: Don't even bat an eyelash. They are not expected to fall 
quite to the levels of the previous front, but it will be coolest in the same areas as was 
the case with the last front. Thus, the immediate east coast from Port Canaveral and 
South will be warmest, with mainly 50Fs expected across the peninsula in other areas. Afternoons could remain in the 80Fs. Winds will be much quicker to shift onshore as well.


SIDE NOTE: The NAM and NoGaPs models are showing for quick tropical development in 
the Northern Caribbean, with a weak low pressure area to form and race north and close to the east coast as the front moves in. For now, disregarding namely because even if so
it would have little impact beyond what has already been stated above.


BEYOND: The boundary will align across the Central Caribbean. As has been the case in 
the long range with the GFS, a bonafide' tropical system is expected to form and impact 
(this time) Jamaica. We shall see.