Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 222006
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
406 PM EDT Mon Sep 22 2014
.Near Term [Through Tonight]...
18 UTC vapor imagery shows an upper low continuing to dig toward
the Gulf Coast. In response, a line of showers and storms have
developed along the surface cold front and are slowing moving to
the SE. This development was well forecast by both the 22/09z and
22/12z WRFs which showed this activity progressing to an area
along and west of a line from TLH-VLD before dissipating once the
instability of the day is lost. As the mid level flow accelerates
ahead of the trough, expect a narrow window for some of these
storms across mainly Southern Georgia to be briefly strong.
After sunset, storms should diminish as drier air aloft continues
to filter into the region. Should be a dry night except for areas
in the Southeast Florida Big Bend which will likely not be cleared
by the frontal boundary and have a slight chance of a shower.
Expect much cooler temperatures into Southern Alabama and portions
of the Florida Panhandle where lows around 60 will be common with
some of the colder spots in Northern Walton County or Geneva
County to have lows in the upper 50s.
.Short Term [Tuesday Through Wednesday Night]...
Upper low will dig into South Carolina overnight and help to push
a cold front through much of the area by early Tuesday morning.
The front is expected to wash out as it reaches the southeastern
Big Bend and high pressure over New England becomes dominant. A
slightly cooler airmass will make its way into the northern
portion of the forecast area, with highs only expected to reach
the lower to mid 80s on Tuesday and Wednesday. The cooler air will
be slower to reach areas south of I-10, with upper 80s expected on
Tuesday and mid 80s on Wednesday.
Any precip should be confined to the southeastern Big Bend through
Wednesday, as showers originating off the northeast Florida coast
migrate southwestward in the northeasterly low-level flow.
.Long Term [Thursday Through Monday]...
The beginning of the extended period will feature a relatively
weak flow pattern aloft across the deep south, with the area
situated between ridges over the Rockies and western Atlantic.
At the surface, northeasterly flow will continue with high
pressure parked over New England and a trough of low pressure
along the eastern seaboard. The northeasterly flow should keep
most of the deeper moisture and showers confined to northeast
Florida. However, isolated activity may reach the far eastern Big
Bend from time to time.
Deeper moisture is forecast to return over the weekend as a trough
deepens over the central states. This should lead to increased
rain chances across the forecast area for Saturday into Monday.
[Through 18Z Tuesday] TSRA will be near/at the DHN/ABY terminals
in the 19z to 23z timeframe before dissipating at sunset.
Potential for a few SHRA to reach VLD/TLH but confidence isn`t
high enough to include in this TAF package. Model guidance
indicates a good chance of MVFR cigs behind the front at VLD/TLH
and possibly ABY before sunrise on Tuesday.
Following a frontal passage tonight, winds and seas will begin to
increase as high pressure builds down the eastern seaboard. Small
Craft Advisory conditions will be possible by Tuesday night, with
winds and seas remaining at or above Exercise Caution levels
through at least Thursday.
Low level moisture will remain sufficient to preclude any Red Flag
concerns over the next several days.
Rainfall totals through Friday are expected to be 1" or less
across the area, with the highest rainfall totals in the eastern
Big Bend. Since local rivers are at or near normal levels, these
totals are not expected to cause rises into flood stage.
.Preliminary Point Temps/PoPs...
Tallahassee 65 87 66 85 65 / 30 10 10 10 20
Panama City 66 88 69 86 68 / 30 10 10 10 20
Dothan 60 84 61 83 62 / 10 10 10 10 10
Albany 63 83 61 82 63 / 20 10 10 10 10
Valdosta 64 85 64 82 64 / 40 20 10 10 10
Cross City 66 88 67 85 67 / 30 30 20 40 30
Apalachicola 70 86 70 84 69 / 30 10 10 20 30