NEAR TERM [Tonight]...
Broad troughing covers the eastern part of the country north of the Mid-Atlantic, while ridging noses east out of the Southern Plains into the Southeast this afternoon.
At the surface, showers and thunderstorms have initiated along both the afternoon seabreeze fronts, as well as a surface trough extending southwest from the Mid-Atlantic to Apalachicola. Dry air aloft has limited the vertical development of these storms and as expected, thus far, thunderstorm gusts have remained well be low severe levels
(30 mph or less). This trend will continue through the day as
storms continue to move east and merge along outflow, the trough,
and seabreeze boundaries. The potential still remains for an
isolated strong to severe storm should the surface forcing promote
healthy vertical development, as dry air aloft would favor evaporative cooling. The best chance for this would likely be somewhere east of Tallahassee in the northern Big Bend and south Georgia later this afternoon. Expect showers and thunderstorms to diminish quickly after sunset.
SHORT TERM [Sunday Through Monday Night]...
There will not be much change in the upper level pattern during this
The ridge will remain parked over TX with a trough axis along the East Coast. That will put much of the Southeast in a northwest flow regime, which means we will need to keep an eye out for MCSs like the one we see dissipating over the TN Valley this afternoon.
At the surface, we will continue to see a stalled frontal boundary just north of the area on Sunday. This front will slip into the forecast area Sunday night and remain there through Monday night.
Some drier air will filter into our northern zones behind the front, but the presence of the boundary should keep showers and storms pretty evenly distributed.
We continue to see discrepancies in the temp guidance between the hotter MAV and milder MET. We decide to weight slightly toward the higher numbers. Even so, although they will be higher than we have seen for much of this summer, heat indices will be lower than our local advisory criteria.
LONG TERM [Tuesday through Saturday]...
The eastern U.S. trough will lift away to the northeast as the upper
level flow deamplifies across the Southeast.
After a couple of days of zonal flow, another trough will move into the eastern U.S. However, this one does not look as if it will extend too far into the Southeast.
At the surface, the subtropical ridge axis will remain south of the region with a trough over the Gulf Coast states.
This feature will help to maintain PoPs at or above climatology.
Temps will be close to normal through the period.
AVIATION [Beginning 19Z Saturday]...
Showers and isolated thunderstorms have initiated this afternoon
and will likely become more widespread and affect KTLH and KVLD
later this afternoon. Expect the best coverage of storms across
extreme south Georgia and the Florida Panhandle, east of AAF.
Although drier air is approaching KDHN and KABY, it will likely
retreat overnight and all terminals will likely see some sort of
MVFR fog/ceiling mixture close to dawn.
With a very weak pressure gradient in place, winds will be light
from the southwest to west with correspondingly low seas.
There will be some enhancement in wind speeds near the coast in the afternoon sea breeze.
Red Flag conditions are not anticipated in the foreseeable future.
The Choctawhatchee river near Bruce and the Aucilla near Lamont are both forecast to inch below flood stage tonight.
All other rivers are already below flood stage.
While convective coverage is expected to increase later in the week, rainfall amounts are not expected to be high enough to produce anything other than minor responses on area rivers.
PRELIMINARY POINT TEMPS/POPS...
Tallahassee 94 76 95 74 97 / 50 20 40 20 50
Panama City 89 78 91 79 93 / 40 10 40 20 50
Dothan 95 76 95 74 96 / 30 10 30 20 40
Albany 95 75 96 74 97 / 40 10 40 20 40
Valdosta 95 74 96 72 97 / 50 30 40 20 40
Cross City 90 74 93 74 95 / 40 20 30 20 50
Apalachicola 88 76 91 77 93 / 40 20 30 20 40