"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".

Monday, November 24, 2014

Larger Rainfall Totals / Narrow Strong Storm Corridor Both "Possible" Tuesday/Wednesday

Cape Canaveral Path Early Monday Morning
TODAY: Warm with near record highs possible. Vero Beach looks to have the best chance of tying or breaking a record as of noon time but the area down into West Palm Beach appears to be yet even warmer still with a current temperature of 87F and other upper 80Fs being shown 'down there'. Guidance shows dry today, but there is a model that has twice now shown the potential for a strong storm near to offshore the Ft. Pierce to West Palm region (perhaps forming off shore), and with another late day over Central Brevard though not as strong. At this time of writing  it is difficult to come upon exactly why this would be; however, it is worth noting.  

TONIGHT-TUESDAY: A frontal boundary now across the Western Panhandle will work south, and as it stands now will not make it as far south as 'Dead Central" or south of there as was mentioned yesterday. Instead it comes closer to wavering near the I-4 Corridor to North Brevard  at the surface, but into the lower to mid-atmospheric levels it is titled back to the north such that at 5000 feet the front is still back over the panhandle. Meanwhile, disturbances CURRENTLY emanating off the mountains of Mexico (see second image below) could ride along the frontal boundary to approach Central Florida as soon as 9AM Tuesday morning, but exactly where the front is laying at that time and the strength of said disturbances will hugely determine the degree of rainfall and where it will fall. 

The latest GFS (Global Forecast System forecast model) is fairly consistent run-to-run showing a swath of largest totals surpassing 2" over a 24 hour period from near a JAX to CEDAR KEY zone south to a line running from near PT. ST JOHN toward SARASOTA on the West Coast (with highest amounts last run over Volusia and Northern Brevard County close to 3", yet the NAM model shows nothing even close to said amounts).

This is of the classic TYPE of "Central Diving Line" or "Dead Central" set ups that might be evolving (as referred to in these posts) for a strong storm to form along the southern periphery of the heavier rainfall totals demarcation. As such will be aware that though upper level temperatures are not as cold as cold be, the best shearing winds near the surface will be right  along and near the southern boundary of heaviest cloud cover and/or rainfall, with the best instability  all south of it. As such, will watch the zone where the best wind shear meets the instability as  shown below  by the purple 'just in case zone'  of 'Dead Central" or 'The Central Dividing Line Zone" anytime from between 11:AM Tuesday through as late as 5:AM Wednesday morning (around the time the actual front actually comes through).

The reason for that latter time frame is that the latest GFS shows a very sharp wind shift line and temperature drop with the front (by as much as a 20F degree temperature fall across the boundary) which could make for a quick 'TOUCH AND GO" spin up like 'tornado in the dark' which are but impossible to forecast or foresee outside of near the time and said type of radar return pops up. Chances are no such creature will evolve though.

SPC (The Storm Predication Center) does have Central Florida in a 'marginal severe threat' on their web page though it is a larger swatch on their page. Would be aware that heavier rain fall and colder air could send outflow into the warmer moist air south of the front which could 'self-induce' a 'quick severe or strong storm' if guidance of GFS is correct
WEDNESDAY: Rainfall could last off and on as late as around 9-11AM Central even behind the front, but RAPID CLEARING commences with the wind shift so by noon-2pm most of Central would be scoured out by much drier and colder air. It is this clearing that might be the bigger story when all is said and done.

The front is forecast to make a rapid drop from Central Florida to clearing South Florida between 7AM and noon. If so, the warmest time of day will be right near to before sunrise. With clearing skies, recovery into the lower 60Fs is possible though it could also be quite breezy with winds from the WNW-NW at 18 G 28 for a time, especially by the early afternoon Wednesday.

WEDNESDAY NIGHT-THANKSGIVING:  Sunset Thanksgiving eve yields clear or 'near clear' with temperatures in the mid-upper 50Fs with slowly dying off winds from the NW-NNW.

Thanksgiving dawns with lows in the mid-upper 40Fs inland and closer to 49F - 52F along the immediate east coast as winds become more northerly with time at about 10-18mph during the afternoon. (hopefully less!).

BEYOND through Weekend: Wind very slowly shifts around to northeast and eventually east-northeast by the end of the weekend at 10-15 mph, but dying off inland at night where winds will decouple and allow colder overnight lows over the interior zones. Dry but with continued 'below' normal high temperatures and near normal low temperatures. Highs warming to the lower-mid 70Fs by Monday but look to be in the upper 60Fs and lower 70Fs Saturday and Sunday. The next cold front could be another week away going into early December. 

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