"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".

Sunday, February 19, 2012

Breezy Today, Showers *Thunder? Possible Mid-Late Afternoon

GFS Forecast for 4pm EST today, showing approximate hand-plotted front positions
Note the dark shades of blue and wind barbs , 20-25 kts of wind equates to winds today in the gusty range toward  25-29mph. Possibly higher near approaching and in any showers or thunder

TODAY: A cold front is entering the Florida Panhandle well before sunrise and will continue through the state, exiting the southern extent in the early-mid evening hours. As of latest guidance and actual radar/satellite trends, it appears that the main wind energy will be restricted to the north half of the state, whereas any thermal instability (also required for respectable storms) will remain over the south half of the state.  In that regards, they do not combine (or overlap) into a 'neat little package' for assured storm generation.

This wind energy even so will be unidirectional throughout the layers of the atmosphere  (from the same direction as opposed to veering with height) which does not bode for rotating storms. Additionally, due to the unidirectional (from the same general direction) wind profiles as one goes higher up in the atmosphere from ground level, there will be little 'forcing' or converging of winds at the lower levels required for forced upward motion into higher levels of the atmosphere (squeezing). Without forcing, thunderstorms might be hard to come by. Also of note, the 500mb vorticity (wind energy) field indicates near NEGATIVE vorticity, which actually plays against storm formation.

With this line of 'reasoning', I'd expect that thunderstorms will be few and far between, limited mainly toward the Tampa Area (not shown)..with perhaps some rumbles within the area of green shown in the above image. 

Increased cloudiness by early afternoon ahead of and along the front will work down the state. Additionally, due to the stronger wind aloft (and cold air), those winds could translate to the surface resulting in breezy conditions today. Highs will be unusual, with near 80F + from South Central to South Florida where cloud coverage will be later to arrive (during peak heating). Dead Central could approach 80F though, especially along the east half of Central.  Increasing clouds and a period roughly from between 2pm - 5pm of light fast moving showers or even some rumbles is possible, extending about as far south as the north shores of Lake Okeechobee toward late afternoon or early evening, all contingent upon the forward motion (timing) of the boundary itself. It is possible that daytime heating will slow down the motion of the boundary, in which case we can tack on up to 2 hours of the shower timing. Given the current upper level trough (system) to the north of the state though, this does not to be a likely or significantly problematic concern.

Do note,  however, that as of this hour the Storm Prediction Center (SPC) located in Norman, Oklahoma has a 'slight risk for severe' as well as a 'see text' in place for the area in green as well. "See Text" essentially is reserved for 'we are watching this area for stronger storms not meeting severe criteria'. Those areas, as it appears, are highly conditional upon formation of storms in the first place. Best chance for thunder might very well be over the Gulf Stream waters and also moving in off the Gulf as far south as Sarasota, but whether any can hold together across interior is the big TBD. 

Any band of showers / the front as it may be, will continue southward into early evening with clearing skies to some degree before dark (Central)..but not entirely so until mid-late evening. Not all areas will see rain today, in fact, most might not.

Temperatures will not fall dramatically behind the boundary (Central/South) as winds become westerly then WNW into the evening, and not really be an issue until after midnight. Lows by Monday morning close to the low-mid 50Fs immediate east coast from the Cape and South Florida, with upper 40Fs to lower 50Fs interior and north with a breezy NW component to the wind early on.

LATER MONDAY: Winds become lighter by late morning through afternoon and veer from NNW-NE-E (by dark)...with near clear skies with highs close to the upper 60Fs right at the beaches (Central), but a bit warmer inland away from the very cool ocean water. Highs over South Florida into the lower 70Fs (at least) most areas. Some clouds might very well work into the east coast and inland by early-mid afternoon as winds turn more easterly.

TUESDAY: Southeast winds and warmer still through Wednesday or Thursday before another front approaches. This front too as it appears will have little impact (if not less) than today's. Another front is then again forecast beyond that time toward next weekend..impact hard to determine at this point (if any).    

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