Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 020202
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
902 PM EST Sun Dec 1 2013
.NEAR TERM [Overnight]...
Approaching weak upper trough is generating a large area of mid
and high clouds over the southeastern states. Looking upstream,
the clouds should persist overnight, severely limiting any
Measurable precip is not expected with the approaching shortwave,
especially considering the amount of mid-level dry air in the
area. However, an isolated sprinkle cannot be ruled out across SE
Alabama or SW Georgia late tonight.
No significant changes to the forecast overnight, with just a
slight downward nudge for min temps given current trends this
.SHORT TERM [Monday Through Tuesday Night]...
A large, broad trough spanning much of the U.S. on Monday will
flatten out and leave essentially zonal flow across the southern
half of the country by Tuesday night.
On Monday, the local area will be positioned at the base of a
shortwave trough, with a positive PV anomaly forecast to traverse
the Tri-State region before turning up the Eastern Seaboard. This
disturbance will likely do very little to the sensible weather
pattern as we`ll be too dry and stable to generate any shower
activity at the surface. As the anomaly passes into the Gulf it
may be able to generate enough troughiness that a few shallow
convergent showers may pop up across the Gulf. In general, the
surface will likely consist of a rather weak pressure pattern on
Monday as the disturbance temporarily weakens the surface ridge.
As the upper flow transitions to zonal across the southern U.S. on
Tuesday, another potent PV anomaly will be diving south through
the Northwest. In response, a strong low pressure system will be
taking shape across the central part of the country, with surface
ridging filling back in off the Southeast coastline. This will
begin our transition to a more southerly flow regime at the
surface. With relatively cool temperatures over land on Tuesday
morning, the warm, moist southerly trajectories will likely create
some light isentropic shower activity throughout the Southeast on
Tuesday. These showers should spread north out of the local area
by Tuesday night.
Temperatures will start near average, gradually climbing to a few
degrees above average both day and night through the short term
.LONG TERM [Wednesday through Sunday]...
The extended forecast will feature the aforementioned potent
shortwave gradually moving southeast, with its forward progress
impeded a bit by a strong upper ridge forecast to build across the
Southern Plains and Southeast. In the fast upper flow between the
trough and the ridge, a PV anomaly originating from a cutoff low
in the Pacific will race northeast, skimming the Southeast on
Thursday. This will likely result in some sort of surface
troughing just to our northwest, and eventually cyclogenesis as
the anomaly passes over the Appalachians. Thereafter, we will
remain in-between the trough and the ridge to round out the
All of this translates to the possibility of a rather unstable
period at the surface with a prolonged period of shower activity
across the Southeast along a quasi-stationary front, likely
enhanced by several surface waves. At this time the bulk of the
rain appears to stay just northwest of our immediate forecast area
but on-and-off rain through Sunday should be expected. The
Southeast will likely be sharply divided with the Tri-State area
sandwiched right in the middle of the unsettled weather to the
northwest, and unusually hot weather to the southeast. If the
forecast pattern holds true, then we`ll likely be dealing with
warmer than average temperatures through the period as a result of
the strong upper ridge. Expect afternoon highs to possibly reach
80 for most spots by the end of the week. Bottom line, expect a
mix of showers and warmer than average temperatures.
.AVIATION [Through 00Z Tuesday]...
A high ceiling around 25,000 feet should gradually lower to around
15,000 feet this evening. However, the relatively thick deck of
mid-high level cloud cover should limit the development of fog and
stratus overnight. Therefore, the forecast calls for VFR conditions
overnight and into tomorrow. We can`t totally rule out the
possibility of some patchy fog if breaks in the clouds develop, but
the chances of that occurring seem relatively low for now.
Northwesterly flow will transition to southerly by Monday night
and will remain moderate through the week. Expect winds and seas
to remain just below headline criteria all week.
With an approaching upper trough beginning mid week and a trailing
cold front Fri into Sat, moisture levels will increase through this
period. Thus, fire weather concerns are not expected through this
Rainfall totals early in the week will be minimal and should not
impact river stages.
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 49 72 47 73 58 / 10 0 10 30 10
Panama City 54 69 57 73 62 / 10 0 20 30 10
Dothan 48 69 51 73 57 / 10 10 20 30 10
Albany 47 68 48 72 55 / 10 0 20 30 10
Valdosta 49 69 46 73 55 / 10 0 0 10 10
Cross City 51 71 45 75 54 / 0 0 0 10 10
Apalachicola 54 69 53 71 62 / 10 0 10 20 10