Flash Flood in Florida, September 16, 2014

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
350 PM EDT Tue Sep 16 2014

.Near Term [Through Tonight]...
After the lull this morning, activity had picked up with
thunderstorms moving south from the northwest. The cold front
located in central Alabama and Georgia will push through our area
tonight. Showers will linger through the evening with clearing by
early morning. There is plenty of moisture in the atmosphere and the
12Z sounding had a PWAT of 2.29 inches, which is 138 percent above
normal. Heavy rainfall is possible and should storms stall, low
lying areas could see flooding.

.Short Term [Wednesday Through Thursday Night]...
A weak frontal boundary will move through the region on Wednesday
bringing some much needed drier air to the region, though very
little in the way of cooler air. As this drier air overspreads the
region through Thursday, expect rain chances to drop to near zero
with partly cloudy skies. High temperatures generally in the upper
80s to lower 90s can be expected, though the big story will be the
drop in humidity.

.Long Term [Friday Through Tuesday]...
By Friday, the mid level pattern begins to stagnate as models show
an upper low cutting off across Northeastern Florida as a weak
ridge builds across the Mid Atlantic States. This type of pattern
will keep partly to mostly skies in place through the weekend with
moderate easterly flow. Low end rain chances can be expected,
especially across the eastern portions of the region.

Late Sunday and into Monday the pattern across the CONUS becomes
highly amplified with a deepening trough across the Eastern US
and a large ridge across the western states. As this pattern
amplifies, the models diverge in whether a cold front will make
its way into the Gulf Coast States and possibly beyond. The 16/12z
Euro stalls the boundary across our region as the main mid and
upper level support lifts out into New England whereas the 16/00z
and 16/12z GFS had some degree of frontal passage late in the
period. Climatology in late September would argue against a front
clearing the forecast area, so will lean closer on a solution
supported by the latest Euro for late in the period.

&&

.Aviation...
[Through 18Z Wednesday]
MVFR conditions this afternoon at all terminals with ceilings
between 1000 to 2500 feet. Brief periods of IFR visibilities are
possible during thunderstorms. Mentioned fog at ABY, DHN and VLD
near sunrise. Confidence of IFR conditions and fog is highest at
VLD. After sunrise VFR at all terminals.

&&

.Marine...
After a brief increase in winds this afternoon, relatively light
winds are expected across the marine area through the remainder of
the week. Winds will shift to easterly and increase to moderate
levels on Saturday as high pressure builds down the Atlantic
seaboard.

&&

.Fire Weather...
Soil moisture and relative humidity will be high this week,
keeping red flag concerns at a minimum.

&&

.Hydrology...
Slow moving storms will continue to deliver locally heavy rainfall
across the region through today. Localized rainfall amounts of 3
to 4 inches could cause minor flooding of low lying areas. This
rainfall will cause some rises of the smaller creeks and streams,
though all rivers should remain well below flood stage.

&&

.Preliminary Point Temps/PoPs...

Tallahassee   70  91  69  91  68 /  50  10  10  10  10
Panama City   74  91  71  90  70 /  50  10  10  10  10
Dothan        69  90  65  88  65 /  30  10  10  10  10
Albany        69  91  66  88  65 /  40  10  10  10  10
Valdosta      69  90  66  91  66 /  60  20  10  10  10
Cross City    70  89  70  92  69 /  60  50  10  10  10
Apalachicola  73  87  74  88  73 /  50  20  10  10  10

&&

.TAE Watches/Warnings/Advisories...

FL...High Rip Current Risk until 11 PM EDT /10 PM CDT/ this evening
     for Coastal Bay-Coastal Franklin-Coastal Gulf-South Walton.

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

&&

NEAR TERM...WESTON
SHORT TERM...GODSEY
LONG TERM...GODSEY
AVIATION...WESTON
MARINE...GODSEY
FIRE WEATHER...WESTON
HYDROLOGY...WESTON