"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".

Wednesday, November 9, 2011

Tropical Storm Sean To Lift North Tomorrow /Cold Front Thursday Night

SEAN positioned over 800NM East of Ft Pierce/West Palm this morning. This image shows Ocean Heat content (which is closely correlated to the SSTs (Sea Surface Temperatures) this morning. Note that any further northward motion will quickly take Sean into ocean waters too cool to support Tropical Storm status (black coloring), although winds will remain at Storm Strength well after it clips Bermuda. The brighter colors in orange denote dry air. Note that Florida is in the dry air in the mid-upper levels to well off shore, indicating that shower activity over the state is not related to Sean.
***REMINDER: Nation wide test of the Emergency Broadcast System (EBS) today at 2:00pm EST. ****

NOW: At 7AM all areas are experiencing drainage flow with some small areas of low patchy fog and a very saturated low level atmospheric moisture profile which quickly dries out  500 ft above the ground, more so above 5-6000ft. Temperatures are in the low-to mid 60Fs with a few upper 50Fs everywhere other than direct beach side from Port Canaveral to Key Biscayne and the middle and lower Keys where temperatures are clinging for dear life on 70-72F.   A few low topped showers linger just offshore the Cape with other showers working into far SE Florida.

TODAY: Sean will meander in place today and eventually begin to lift northward tonight. High pressure builds NE ward from the SW Gulf as the high pressure wedge down the Eastern Applachians that had been creating the pressure gradient retreats NE ward as well ahead of an approaching cold front and that front's supporting upper level trough.

Winds today to become more NNE at 10-20mph with strongest inconsequential winds down the Barrier Islands/Intracoastals along the entire east coast, with a period of such winds in the mid-afternoon inland as mixing works out the low level inversion that is trapping the moisture close to the ground this morning. Low topped showers, mainly sprinkles but the dominant mode will be decks of flat topped stratocu mainly over the Southern Half of the state, with more dense clouds of various altitudes across North Florida ahead of the approaching frontal boundary. Temperatures like the past two days, with highs at the beaches in the mid-upper 70Fs  with some very low 80Fs interior/west/and south Florida. All in all, highs will be dependent on cloud coverage (where it will be located) during peak sun angle hours.

TONIGHT/EARLY THURSDAY: Winds become light NW well after dark and shower chances end with cooling temperatures everywhere. There could be some lower ground fog almost anywhere by morning with dewpoints remaining steady state close to the ambient air temperature, with lows in mid-50Fs everywhere except near any body of water where lows will be in the low-mid 60Fs.

Morning enhanced infrared satellite image shows Sean well to the east of Florida and a projected track for starters. Surface front in light blue and the high pressure building into the Gulf and down the Appalachians. Sprinkles possible, mainly the South Half of State, with patches of stratocu resulting in sky conditions varying from sunny to mostly cloudy for brief periods in a few select TBD locales. Meanwhile, Alaska is dealing with a No-Named Hurricane Equivalent Storm of its own, one perhaps of intensity this time of year never equaled except maybe once in recorded history.

THURSDAY: NW Winds of 10-15mph during the afternoon with highs near 80F to lower 80Fs, but cloud cover will be a key factor in this variable, especially across Dead Central where it might end up being in the lower to mid 70Fs. Front appears will go through Panhandle dry. As high pressure in the Gulf continues NE ward (and pushes Sean further north and east), pressure gradient winds behind the front will already be in place over the Western Gulf. Moisture convergence during a brief window of opportunity behind the departing high and ahead of the front could result in some sprinkles or showers 30 miles either side of the Magic Dividing Line (MDL) running from Tampa Bay to Port Canaveral from early afternoon to sunset 'ahead of' and 'as' the front passes through.

THURSDAY NIGHT/EARLY FRIDAY: Cold front then to cross from NNW-SSE down the peninsula, crossing the MDL around 10:30pm. Front to be followed by PERHAPS gusty winds right along both the West and East Coasts from JAX - Ft. Pierce (on the east side) of 18-25mph for a few hours overnight. It appears these will stay offshore the coast further south, and be greatly reduced by sunrise or shortly thereafter as the high pressure continues NNE ward.

FRIDAY: Cool all day with highs in the upper 60Fs to near 70F along the MDL and cooler North with some highs north of I-4 never making it out of the 50Fs. South Florida / Keys should reach the Middle 70Fs..all with north winds of 15-22mph making for a very cool, fall like day under mostly clear skies.

FRIDAY NIGHT: Circulation around the high which will work well NE ward to the NW Atlantic and SW ward into the SW Gulf of Mexico results in NNE-NE winds overnight. The immediate east coast from Port Canaveral and South should level off in the quick temperature fall that will ensue with the setting sun, and actually warm a few degrees prior to sunrise, remaining essentially in the lower to mid 60Fs while inland lows vary from the low 50Fs to mid 40Fs as far south as Okeechobee, and even cooler from Ocala toward the Big Bend and Panhandle region.

SATURDAY: With a cool/cold start early winds will become ENE everywhere by late morning with a rapid warm up into the 70Fs with sunny to scattered skies working onshore by early afternoon. Winds in the 10-15mph range and 70F's to make for a stellar weekend with similar conditions on Sunday.

BEYOND: Much of next week will be more of the same with overnight lows gradually warming as air mass modification (rising dew point temperatures) is prolonged with continued ENE-E flow. Any windier conditions (above 18mph) will be restricted to the Southern 1/3 of the state. There might be some low topped sprinkles toward South Florida by early to mid next week, but not worth the mention in a forecast highlight.

NEXT WEEKEND: So far, it continues to look like the weather this coming weekend won't be that of the following weekend per the GFS Model. Warmer with overnight and daytime highs remaining in the 70Fs at the coast and 60Fs inland with highs near 80F or above interior and west, cooler near the east coast everywhere . E winds becoming ESE-SE as the next front will be on the approach by next Thursday (right on cue). It still appears this front will reach Central, this time becoming absorbed quickly in the prevalent dome of high pressure over the southeast States toward coastal South Carolina. Not once in the past 4 days (and 16 model runs) has the GFS showed a clear cut frontal passage. Numerous showers  with moisture depth reaching upward toward 8000 ft (as opposed to a shallower 5000 ft) would result in measurable rainfall, mainly over the Southern 2/3 of the state with the higher totals within 40 miles of the East Coast from Brevard County and South.  

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