NEAR TERM [Through Tonight]...
A line of heavy showers and thunderstorms is breaking up as it makes its way across the forecast area. The environment is not favorable for severe weather and a lack of sufficient vertical wind shear is preventing updrafts from being sustained. Widespread severe weather is not expected, but a couple of these storms have demonstrated the presence of a decent updraft, so a strong cell with the potential for small to marginally severe hail cannot be ruled out. Some higher gusts may be present with some of these cells as well, but so far the highest gust reported has been about 35 MPH which is more than 20 MPH lower than our severe criteria of 58 MPH.
SHORT TERM [Tuesday through Wednesday]...
Much drier air, mainly in the mid to upper troposphere, will advect
into the region behind a trough exiting to our east on Tuesday. The dry, sinking northwest flow will suppress deep moist convection in all but a few cases.
The tightly-clustered MOS PoP guidance is 20% or less for both days, and even the Convection Allowing Model (CAM) ensemble has a PoP of less than 10% for Tuesday.
With less cloud cover, high temperatures will be above climo, in the mid to upper 90s. Fortunately the warmer temperatures will be accompanied by slightly lower boundary layer moisture (primarily due to deep mixing) during the afternoon hours, which should prevent reaching heat advisory criteria.
Still, heat index values may approach 105 deg in some locations, especially Wednesday afternoon.
LONG TERM [Thursday through next Monday]...
On the large scale, the GFS and ECMWF maintain a central CONUS
ridge/east coast trough through the period. A "backdoor" cold front
is scheduled to pass through our forecast area on Friday, followed
by a return to dry, sinking northwest flow aloft. The WPC/GFS/ECMWF
consensus PoP is near climo Thursday and Friday (about 40%), then
below climo thereafter (20% or less). Both models have backed off on
upstream MCS development.
Above climo high temperatures (mid-upper 90s) will continue Thursday and Friday, with Thursday being the warmest. The GFS maintains a warm, dry airmass across our region after Friday`s frontal passage, while the ECMWF forecasts slight cooling. A blend of these two results in near climo temperatures.
AVIATION [Through 18Z Tuesday]...
Mostly VFR conditions with brief periods of MVFR-IFR as a line of
thunderstorms crosses the forecast area. Showers behind the storm
may carry with them lower cigs and vsbys as well. Much more
scattered coverage east of the main line near TLH and VLD.
Later tonight fog development is expected where moisture from today is high and where winds will calm overnight at all sites except ECP.
A fairly weak pressure gradient will exist across the coastal waters
for much of this week, tightening slightly as a cold front approaches from the north Thursday and Friday.
There could still be some significant wave heights around 3 ft today, but they will subside to 1 to 2 feet by tonight, and remain below 3 ft until Thursday night and Friday.
A warmer and drier airmass will begin to overspread the region of
Tuesday and continue into the late work week.
However, relative humidity levels will remain above critical thresholds and Red Flag conditions are not anticipated this week.
Mossy Head (Shoal River) and Hahira (Little River) went above action
stage due to the recent heavy rains. However, they are unlikely to
increase much farther since today will be the last day of widespread
rain. Any non-river flooding for the remainder of today will be very
localized, and limited to low-lying, poor drainage areas.
PRELIMINARY POINT TEMPS/POPS...
Tallahassee 71 93 72 94 73 / 10 10 10 20 20
Panama City 75 88 76 89 77 / 10 10 10 20 20
Dothan 70 94 74 96 75 / 20 10 10 20 20
Albany 70 94 73 97 74 / 20 10 10 20 20
Valdosta 71 95 71 98 73 / 20 10 10 20 20
Cross City 72 91 70 92 72 / 10 20 10 20 20
Apalachicola 75 87 75 88 76 / 10 10 10 20 20