"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 14, 2011

Slight Chance of Coastal Showers Tonight, Possible Showers/Thunder Tuesday

Red areas show Moisture working north and up the state from South Florida, moisture being drawn north from the Gulf ahead of a frontal boundary, and lastly moisture converging ahead of the frontal boundary itself across the Southern Plains through the Ohio Valley over night tonight.

LATE TODAY/NIGHT: High pressure ridge axis at the low levels extends across North Central Florida and will drop slowly south and off shore through Tuesday as a frontal boundary approaches the state very slowly through early Thursday. In the short term (late today and through tonight), moisture is being pulled northward around the western periphery of this low level high pressure center located near Bermuda, while warm air aloft is also being drawn north and up the state around a mid level ridge located close to the low level ridge. Moisture with a lifting cap aloft overnight could promote low topped ocean showers near the Treasure and Space Coast under the gentle over-running or roughly north of Ft Pierce to Port Canaveral at almost anytime between 5pm and 8AM Tuesday morning. Meanwhile, a very shallow subsidence inversion should take shape fairly quickly with the setting sun further from the coast and warm ocean waters. During the late evening, expecting low ceilings of stratus clouds to form, with a few areas of patchy dense fog well inland and away from heavily populated areas where low level cooling will be greatest especially toward West Central and north toward the western Subs of Orlando, Ocala, Gainesville, and much of interior North Florida/Panhandle. There could be some low stratus or thin fog as well almost anywhere prior to midnight, but believe the prevalent mode closer to the east coast and especially SE Florida will be broken to overcast sky conditions of stratus clouds.  Net result, warm overnight lows in the low 70Fs with dewpoints already approaching that level this afternoon as can be seen below:

Pink areas indicate 70F + dewpoints as of now (while typing). The temperature tonight will not fall below those levels....and will unlikely make it north of the aforementioned low level ridge axis which will drop to central Florida, or roughly the Central Diving Line (CDL) from Port Canaveral to Tampa Bay area. Showers most likely from the Port toward Ft. Pierce tonight, with the most dense of fog in the areas of Green and Yellow shown above where surface temperatures will cool the most under warm air over-running.

TUESDAY: Clouds will be slow to break initially, and hoping to be see plentiful sun by 11-noon. Winds generally SE-SSE at 10-15mph, with highs inland in the lower - mid 80Fs and closer to those of today along the immediate coast (near 80-82F) prior to development of additional clouds. Inland highs are tricky, and suspect that mid-80Fs might be optimistic for the warm air lover, since heating could simply lift and break the stratus deck and transition it  to plentiful cumulus clouds, with only a brief period (less than one hour) of full sun is that's possible. 

With the lower sun angle given the time of year (the longest days are only a little more than a month away)...lower 80Fs seems more likely. SSE-S winds along the east coast combined with a weak west coast sea breeze could result in a sea breeze convergence well away from the coasts toward 4pm, but some showers could form along the west coast sea breeze mainly toward the northwest side of Lake Okeechobee initially. Additional showers and possibly a very thunderstorms as well to run from SE Polk county, through Western or Central Orange County, and north toward the I-4 including  ONF (Ocala National Forest) and Gainesville. The GFS implies  the deepest showers of convective nature will exist along and north of I-4 after 6pm, with some activity moving offshore from near St. Augustine south toward Daytona.  However, that will be contingent   upon how parallel to the coast the surface winds are at this time. Any stronger on shore wind component north of Port Canaveral will kill convection given that ocean temperatures off shore are running in the mid-60Fs there. If winds maintain a South to SSW component or attain one toward sunset, showers or thunder could work off the east coast given that the low and mid level ridge axis' will by now be located near the Southern Shore of Lake Okeechobee. 

WEDNESDAY: Morning fog or stratus is possible once again, but most likely stratus clouds as surface winds could be stronger ahead of an approaching frontal boundary. Timing has been slowing down from run to run (and from time to time), and if it slows down even 6 hours more, fog will again be possible and be more widespread than tonight (overnight on Tuesday).  Although winds on Wednesday  will be S to SSW to possibly SW later in the day, record highs might be tough to attain due to expected cloud coverage, If so, the most likely areas will be near NE Florida along and north of I-4 north of Sanford toward St Augustine. Continued SSE -SE winds over South Florida will preclude record highs in this area, although the region inland of Ft Myers/Naples might come close as well.

THURSDAY: Frontal boundary now expected per model agreement to reach Dead Central toward the MDL (Magic Dividing Line) ever so appropriately but admittedly very' unprofessionally'  labelled by the writer this go around, as it appears it will be within that zone the front will not be able to penetrate much further south. Showers and thunder will be possible along and ahead of the front is it drops from North to North Central from late morning through Sunset, and eventually running into the low level ridge axis remaining across far South Florida's 'saving grace ridge' toward Southern Dade and stacked to 10,000 ft. A frontal passage across north Florida will become near Neutral toward 30 miles either side of the MDL. With that said, best chances of showers and just maybe some thunder as far south as the Eau Gallie Cauesway, but watching to see if this chance won't extend as far south as Route 60 (Vero Beach). A few coastal showers SE Florida but it appears this go-around, most of the state south and near Lake Okeechobee will see very little rainfall from this front, namely because precipitation with it comes along moisture convergence with the boundary, of which there will be none in this area. It is also possible there will be some near record warm overnight lows on Thursday morning...(mid-70Fs), South Central. 

FRIDAY:  High pressure in the low to mid-levels rapidly builds eastward across the Deep South and becomes centered toward the Eastern Carolinas by Friday morning. A wind surge is being depicted to impact those areas only that are behind the locked and decaying frontal boundary, or from Sebastian Inlet and north, if not only the Melbourne beach area and north.  Winds of 18-28mph possible through mid-afternoon. A few showers are possible as well anytime on Friday mostly near where the boundary dissipates (East Central/Space Coast).

SATURDAY: Continued shower chances in the same areas and possibly spreading back toward NE Florida, or roughly anywhere north of a line running from Ft. Pierce to Sarasota, most likely east side. Shower chances should wane by sunset Saturday night, with only some possible sprinkles remaining for Sunday, although this might be optimistic. Cloud coverage might remain an issue over the weekend though either way.


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