Area Forecast Discussion
Issued by NWS

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

934
FXUS62 KTAE 210653
AFDTAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
253 AM EDT Mon Jul 21 2014

.Near Term [Through Today]...

The 11 pm EDT regional surface analysis was complex, as a wavy,
quasi-stationary front over the Southeast was rather ill-defined.
It extended from a broad, weak low pressure system (1014 mb) in
Southern MS, east-northeastward across Central AL and GA. There
was also a subtle trough along the FL Panhandle Coast. Vapor
imagery and upper air data showed ample moisture over our region,
though not the kind of deep layer moisture (and tropical
connection) that often results in widespread heavy rain for our
region this time of year. A fairly potent, positive-tilted trough
was translating southeastward over the Southeast, and extended
from Central TN to the TX coast.

After an evening lull, scattered showers and thunderstorms had
begun to develop off the FL Panhandle Coast, and all indications
are that this trend will continue through the morning hours (given
the ample moisture and synoptic/mesoscale forcing). Our forecast
follows our 11 pm EDT ensemble of Convection Allowing Models
(ECAM) closely, with PoPs ranging from 40 to 80% today. The
highest PoP will be along the FL Panhandle and North FL coasts.
The large scale environment (with weak winds aloft and somewhat
marginal lapse rates) doesn`t appear conducive for severe storms.


.Short Term [Tonight Through Wednesday]...

The early part of the week will feature an upper level low just
west of our forecast area slowly retrograding westward to near New
Orleans by Wednesday. The stalled surface front across the area
will slowly lose its definition and mid-upper level ridging will
temporarily build back in with slowly rising heights. Therefore
the general trend should be slightly higher temperatures and lower
PoPs on Wednesday as compared to Tuesday.

For Tuesday, PWATs will remain around 1.9 inches (near normal)
over the eastern half of the area, and enough forcing for ascent
should exist to contribute to numerous showers and storms again
in those areas. Slightly drier air in the western half of the area
with PWATs closer to 1.7 inches (25th percentile) will likely lead
to lower convective coverage. Therefore, we included likely PoPs
(>55%) across the east with lower values west.


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

The mid/upper level trough will persist across the local region
through the extended period. The trough will be wedged between
the Bermuda Ridge and strong ridging centered over the Desert
Southwest. Temperatures along with rain chances are expected to be
at or above climo each day.

&&

.Aviation...

[Through 12Z Tuesday] Other than periods of IFR/low-end MVFR CIGS
at KDHN and KABY overnight through mid morning, the main focus
will be SHRA/TSRA. We expect SHRA/TSRA at KECP before sunrise,
lasting through at least mid morning. Similar conditions are
expected at KTLH late morning through early afternoon, and KVLD
mid to late afternoon. The rain will coincide with brief periods
of low VIS/CIGS and gusty winds. While scattered SHRA/TSRA will
develop around KDHN and KABY this afternoon, the probably is
currently too low to forecast TSRA at these sites. A return to
just isolated TSRA and generally VFR conditions is expected this
evening and overnight.

&&

.Marine...

Slightly higher winds (10-15 knots) lingering into today should
keep seas elevated around 2-3 feet, and significant wave heights
in that range are still being observed at the offshore buoys.
While this won`t rise to SCEC levels, it should still create
choppy conditions for mariners. Given the possibility for
lingering breezy winds and the active rip currents yesterday, our
general outlook for today is for a continued high risk of rip
currents in Walton, Bay, and Gulf counties as active rip channels
from yesterday may continue to be activated. Overall, though, the
trend in the forecast is for winds to gradually diminish along
with wave heights.

&&

.Fire Weather...

Rain chances will be quite high this week, especially in FL today.
Red Flag conditions are not expected this week.

&&

.Hydrology...

With such deep layer moisture, heavy rain rates are expected today.
However, flash flood guidance is still quite high across most of our
region, and we expect convective cells to propagate quickly enough
to avoid excessive accumulations on a wide scale. The exception
would be if these high rates were to occur for a significant amount
of time over urban areas. The probability of this happening is not
high enough for a Flash Flood Watch, and we will just have to
monitor this as the day goes on. The Shoal River at Mossy Head is
above bankfull stage and will continue to be monitored. All other
rivers are also currently below flood stage.

&&

.Preliminary Point Temps/PoPs...

Tallahassee   87  71  92  72  93 /  50  30  60  30  50
Panama City   86  75  89  75  89 /  80  20  50  20  40
Dothan        87  72  91  72  93 /  40  20  50  30  40
Albany        88  71  92  72  93 /  40  40  60  40  40
Valdosta      87  70  91  71  95 /  60  50  60  50  50
Cross City    87  71  92  72  93 /  70  50  60  40  40
Apalachicola  86  74  88  74  89 /  70  30  50  20  40

&&

.TAE Watches/Warnings/Advisories...

FL...High Rip Current Risk until 8 PM EDT /7 PM CDT/ early this
     evening for Coastal Bay-Coastal Gulf-South Walton.

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

&&

$$

NEAR TERM...FOURNIER
SHORT TERM...LAMERS
LONG TERM...BARRY
AVIATION...FOURNIER
MARINE...LAMERS
FIRE WEATHER...FOURNIER
HYDROLOGY...FOURNIER






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.