NEAR TERM [Through Today]...
High pressure will continue to ridge down the Appalachians into the
area with northeasterly flow prevailing across the region. Some
Atlantic moisture has drifted into the region today and is responsible for some scattered clouds across South Central Georgia and the Florida Big Bend.
With light northeasterly flow expected overnight, should see another cool night for much of the area. The only concern is for low cloud cover in the eastern third of the region late tonight keeping temps there a little warmer.
Outside of areas of cloud cover, lows are expected to be in the mid to upper 50s in Southeast Alabama and Southwestern Georgia and around 60 in the Florida Panhandle.
SHORT TERM [Sunday through Tuesday]...
Sunday and Sunday Night. The large scale longwave pattern is
dominate by nearly zonal flow from Ern Pacific Ewd into Ern states,
then ridge from OH River Valley Swd into NW Gulf of Mex. This
pinches and cuts off trough from Ern seaboard into Wrn Atlc. Finally
broad W-E ridge across old Mex, Srn TX into Wrn gulf of Mex. At
surface, high in Atlc east of New England with axis swwd down spine
of Appalachians thru high over NE GA placing local area on Srn
periphery. This pushes low Ewd into Atlc off of Carolinas. old front
from low in Nrn Ontario SSW down MS Valley into E/Cntrl TX.
All this places local area in dry NLY flow aloft and ENE flow below. This drier and relatively cloudless airmass translates to a cool start
for the day. By night, upper low within tough opens up and drifts
newd with local flow becoming weak WNW. At surface, Carolina low
lifted newd allowing high pressure to settle Swd. Cold front nudges
a little further Swd albeit absent upper dynamics, in a weakened
state. Will go with slight chance POPs marine area thru period.
Continues cool with high around 80 north to 85 degrees south. Lows
in the low to mid 60s.
On Monday, models imply that some shortwave energy will move across SE Conus very late Sunday night into Monday helping upper ridge to evolve into a weak broad trough over Gulf region and adjacent Atlc pushing frontal boundary into our area where it likely stalls W-E. This shift of trough into Atlc splits surface ridge leaving a weaker area of high pressure locally. this weaker area plus passing
shortwave allow moisture ahead of front to moves SEWD into mainly
our Wrn CWFA.
Will go with 0-40% NE-SE POP gradient. Highs in the mid 80s.
On Tuesday, broad upper trough begins to weaken and is replaced by
upper ridge building into SE region drying area out.
Will go with 20% POPS. Highs in the mid 80s.
LONG TERM [Tuesday Night through Saturday]...
The long term forecast is tricky as some models shows a tropical
system possible impacting our area later in the period. Hence
overall confidence is low.
The period begins with ridging over Ern states with axis from Canadian Maritimes SSW into AL/GA and a trough along Ern seaboard. At surface, high pressure dominate se region with high centered in Nrn TN Valley.
Dry beginning except for chance precip over mainly waters.
The upper ridge will shift Ewd over the wrn Atlc with axis over
Bahamas Thurs into Sat as a strong trough digs SEWD over the Nrn
Plains and Cntrl Rockies and becomes cutoff from the main upper flow over Nrn tier Conus.
The position of Bahamas ridge allows deep tropical moisture to advect Nwd from Wrn Carib/SE Gulf of Mex around periphery of ridge.
At surface, low may develop over NW Carib/SE Gulf and gradually lift Nwd over Ern Gulf. Here models diverge with GFS much more bullish than ECMWF on this scenario. The 12z GFS develops an area of low pressure over the Carib Sea on Tues, takes over Haiti on Wed, NEWD (?) across Cntrl FL Thurs night into Fri then off this coast Fri night.
This would likely set up up local area for sharp NW-SE POP gradient with a good chance of convection and possibly flooding Ern Big Bend and adjacent waters Thurs into Fri.
Latest ECMWF scenario seems to keep wetter scenario to our west and southeast and UK Met has also backed off.
Until I see more evidence of model consistency or that the stronger GFS is initializing the best, I will lean towards weaker scenario and only gradually increase winds and POPS which follows thinking on surrounding offices.
By Sat Eve ern trough has moves offshore to be replaced by ridge and a drying trend.
Will go with 0-30% thru Wed night, 20-40% Thurs-Thurs night, 30-50% Fri then 20-30% thru Sat.
Highs generally in the mid 80s, lows in the mid 60s increasing slowly to around 70 by Sat night.
For now, winds over mainly offshore marine area will increase to exercise caution on Wed then likely SCEC nearshore and SCA offshore into Fri. Seas will gradually build to SCA offshore by late Thurs.
All this of course is highly dependent on actual track/intensity of any tropical system.
VFR conditions are anticipated to prevail through much of the current TAF cycle. The only potential restrictions look to be at VLD in the early morning hours with a combination of low ceilings and visibility at the MVFR level.
All sites should be VFR after 15z.
Breezy northeast winds at SCEC levels are likely to continue through tonight.
A weakening of the high pressure ridge along the east coast should allow winds to relax thereafter, with values below 15 knots and subsiding seas.
Winds and seas could begin to increase to SCEC then SCA levels Wed into Fri dependent on possible evolution of tropical low. (see Long Term Discussion above).
Though relative humidity values will be lower than the past few days, still only expect minimum values Sunday in the 40 to 45 percent range. Thereafter, a moistening trend will begin.
The Choctawhatchee River at Caryville has crested with Bruce likely
to crest on Monday afternoon with both points below flood stage.
All other rivers remain below action stage and should do so into the
middle part of this coming week.
Beyond this time, much uncertainty exists in the forecast regarding future rainfall amounts.
PRELIMINARY POINT TEMPS/POPS...
Tallahassee 61 85 64 86 67 / 0 0 10 20 20
Panama City 64 83 69 84 71 / 0 0 10 30 30
Dothan 57 82 62 84 65 / 0 0 10 20 20
Albany 57 82 61 85 64 / 0 0 10 20 10
Valdosta 60 84 63 86 64 / 0 10 10 20 10
Cross City 65 86 63 86 66 / 10 10 10 30 20
Apalachicola 67 83 70 83 72 / 10 10 10 30 30