Area Forecast Discussion
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064
FXUS62 KTAE 151351
AFDTAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
951 AM EDT Mon Sep 15 2014

.Near Term [Through Today]...

Shower activity over the gulf is dying down this morning, however,
southerly winds will continue to push moisture inland throughout
the day. The 12Z sounding had a PWAT of 2 inches which is 121
percent above normal. This moisture combined with the stationary
front located in the northern part of our CWA will lead to
widespread thunderstorm coverage this afternoon. While widespread
flooding is not expected, localized heavy rainfall is possible.
Highs will be near 90 today.

&&

.Aviation...
[Through 12Z Tuesday]...

VFR conditions are expected outside of thunderstorms today. Vicinity
showers and tempo MVFR conditions this afternoon for all
terminals.

&&

.Prev Discussion [438 AM EDT]...

.Short Term [Tonight Through Wednesday]...

The end of the very stagnant synoptic weather pattern which has
dominated our region for much of the month of September thus far is
finally in sight. This pattern, which has resulted in unseasonably
warm and wet conditions in the absence of any organized tropical
activity, has indeed helped many areas catch up in rainfall from the
record or near record dry conditions this past meteorological
summer. For example, Tallahassee had its driest period of June,
July, and August of all time with with only 8.99 inches of rainfall,
which happens to be the only time on record this period has ever been
below 10 inches. Through Sept. 14, 5.14 inches of rain has already
fallen this month, and if 3.86 inches of additional rain were to
fall during the next 3 days (which is certainly possible), then the
September rainfall would already exceed that of the entire summer.

The defining features of this month so far (which is also averaging
nearly 3 degrees above normal in temperature every day) have been
characterized by a weak Sfc pressure gradient and a stubborn "dirty"
upper level ridge (with plenty of deep layer moisture (PWATs between
1.8" and 2.2") continuing to flow into the CWA from western Atlantic
and Gulf of Mexico. This ample moisture will remain in place across
the region through at least Tuesday night, and with the upper ridge
finally expected to break down and retrograde westward, a steepening
upper level trof will initially help energize the above mentioned
Sfc boundary, increasing the chances for another period of heavy
rainfall on Tuesday, possibly lingering into Tuesday night. While
mean storm total rainfall amounts are generally expected to be in
the 1" to 3" inch range across the entire region, isolated amounts
of 3" to 5" or even 4" to 6" could be possible (especially near the
coast of the FL Panhandle and western Big Bend) before all is said
and done on Wednesday. However, since these higher amounts should be
isolated as well as spread out over 3 days, the threat for any
widespread flooding appears minimal at this time. Additionally,
during each successive run of the Global Models during the past few
days, the trend in both the GFS and ECMWF has been to accelerate the
steepening of the trof which will help push the stalled out boundary
through as a cold front on Wednesday and Wednesday night. This will
put a quick end to the heavy rain chances, and may even bring a slight
taste of fall to the region by the end of the week.


.Long Term [Wednesday Night Through Sunday]...

As the upper level trough deepens and moves south, the stalled
frontal boundary will move off to the southeast bringing in slightly
drier air. With the drier air behind the trof and cold front, PoPs
drop into the 10 to 30% range for the upcoming period. We will see a
taste of cooler temperatures with highs in the mid 80s and lows in
the mid to upper 60s.


.Marine...

With a stalled out frontal boundary to the north of the coastal
waters, the surface pressure pattern will remain stubbornly tight
today into Tuesday, allowing for south to southwest winds of 10 to
15 knots and 2 to 4 foot seas. Thereafter, winds and seas will
slowly diminish behind the cold front on Wednesday and Thursday, as
the winds become offshore. Then, by the end of the week and into
next weekend, a strong ridge of high pressure will build in to the
northeast of the marine area, creating a tight pressure gradient
once again, with favorable conditions for easterly surges.


.Fire Weather...

Red flag conditions are not expected at least through the end of the
workweek.


.Hydrology...

As mentioned above, a widespread 1 to 3 inches of storm total
rainfall (with isolated higher amounts) is expected to fall across
the HSA during the next few days. While this may cause some rises on
our area rivers and streams, it is unlikely to bring any of them to
flood stage, especially with the highest rainfall amounts expected
closer to the coast.

&&

.Preliminary Point Temps/PoPs...

Tallahassee   90  72  89  70  91 /  70  40  70  50  30
Panama City   89  76  87  74  88 /  70  50  70  50  20
Dothan        89  71  89  69  90 /  60  40  60  30  20
Albany        92  71  90  69  90 /  60  40  60  30  20
Valdosta      90  71  89  69  90 /  60  40  70  50  30
Cross City    91  71  87  69  88 /  60  30  70  50  40
Apalachicola  87  77  86  76  86 /  70  50  70  50  30

&&

.TAE Watches/Warnings/Advisories...

FL...High Rip Current Risk through late tonight for Coastal Bay-
     Coastal Franklin-Coastal Gulf-South Walton.

GA...None.
AL...None.
GM...None.

&&

$$

NEAR TERM...WESTON
SHORT TERM...GOULD
LONG TERM...WESTON
AVIATION...WESTON
MARINE...GOULD
FIRE WEATHER...BARRY
HYDROLOGY...GOULD






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