NEAR TERM [Rest of Today]...
At upper levels, a large positively-tilted trough dominates the eastern 2/3 of North America. A 130-kt jet is noted at 250 mb over KY and WV.
Flow across the Southeast is out of the SW and this means there is no real push to get this front out of the area. It has been stalled over the region for a day or so and currently extends from the Eastern FL Panhandle to South Central GA. Patchy dense fog will once again be possible along and ahead of the front around and near the FL Big Bend this morning and we have already seen the visibility drop at Perry, Quincy and Thomasville. We will monitor for a possible advisory if these lower visibilities become more widespread.
QG forcing will increase over the front today in the form up upper
level divergence in the right entrance region of the jet. Some
weakening DPVA will also work its way into the region.
This should allow another round of showers to develop in the vicinity of the front once again today. The first area to see showers should be the Panhandle this morning as remnants of an MCS moves east across the northern Gulf of Mexico. PoPs will be highest in this area (50-55) and taper off to the north and east. Instability should be sufficient for thunderstorms only across the warm side of the front in the FL Big Bend.
Like yesterday, there will also be a fairly large temperature gradient across the boundary with northwestern areas seeing afternoon temps in the mid to upper 70s and the Suwannee Valley reaching the upper 80s to possibly 90. A stronger cold front, currently over the Ohio Valley and Southern Plains, will approach our northwestern zones by evening.
SHORT TERM [Tonight through Monday]...
A surface cold front is expected to move south and east of the forecast area by tonight, and model time cross sections show
considerable mid-level drying by 12z Sunday.
Although the region will remain in the right entrance region of a 100-120 knot upper level jet streak, the lack of low-level forcing combined with a drying column should preclude much rainfall through Sunday night. A few light showers can`t be ruled out, especially lingering this evening or over the coastal waters on Sunday and Sunday Night.
The approach of another shortwave trough aloft and the development of a weak surface low or inverted trough along the north-central Gulf
coast on Monday should lead to an increase in PoPs through the day
and into the overnight hours.
Despite a cold front transitioning through the forecast area Saturday, temperatures are not expected to cool that much into Sunday. Much of the troposphere above 900mb will still see southwesterly flow which
will limit the SE progress of cooler air and weaken the temp gradient with time. Therefore, temperatures should be relatively close to normal for this time of year.
LONG TERM [Monday Night through Friday]...
The next in a series of upper level disturbances embedded in the
deep southwest flow ahead of an amplifying trough will lift from the
western Gulf and across the southeast CONUS Monday and Tuesday.
This will bring widespread rains to the Tri-state region both days. Rain will end from west to east Tuesday night into early Wednesday as the axis of the upper trough and associated cold front sweep through the area.
Surface high pressure along with a colder and much drier airmass will build in for the remainder of the week.
For Thursday and Friday we expect to see the coldest minimum temps since the middle of May with readings in the mid to upper 40s. Highs will range from the lower to mid 80s Monday dropping into the lower to mid 70s for Thursday and Friday.
AVIATION [through 06 UTC Sunday]...
IFR conditions will develop overnight at VLD, ABY and ECP with
MVFR expected at DHN and TLH.
These ceilings will lift by mid morning with VFR ceilings then scattering out by evening.
Periods of showers will be possible at the terminals, but chances for
thunder were considered too low to mention.
There may be a brief increase in northerly winds behind the surface cold front tonight.
Borderline SCEC winds are possible (15-16 knots) in the western half of the coastal waters, but this may not be enough to warrant a headline.
Relatively light winds and seas are expected again until a stronger cold front mid-week.
SCEC winds appear likely by late Wednesday and into Thursday, with
advisory conditions possible.
Dispersion indices will be low to the northwest of a front today, mainly in the teens and 20s.
Sunday, in the wake of the cold front, humidity levels will drop.
However, red flag conditions are not expected over the next few days as RH values will not get low enough.
A drier airmass will arrive late next week.
Rainfall through the weekend is expected to be light, with no flooding problems expected on area rivers and streams.
PRELIMINARY POINT TEMPS/POPS...
Tallahassee 82 62 82 62 81 / 40 20 10 10 30
Panama City 81 62 79 63 79 / 50 20 10 10 40
Dothan 77 53 76 54 78 / 40 10 10 10 30
Albany 79 55 78 54 79 / 40 20 10 10 30
Valdosta 83 61 80 61 80 / 30 20 10 10 30
Cross City 87 66 83 65 84 / 20 20 20 20 40
Apalachicola 82 65 78 65 79 / 40 20 10 10 40