Flash Flood Warning 17, NWS Tallahassee, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
414 PM EDT MON SEP 28 2015

.Near Term [Through Tonight]...
An 18Z analysis shows the broad area of low pressure about 200
miles west southwest of Tampa which will slowly move north through
the period. While there is little chance of this becoming a
tropical cyclone, there is already a large moisture plume in the
northern Gulf ahead this system. A persistent band of rain has set
up over southern Alabama and the far western panhandle, where rain
totals have reached 2-4 inches (see hydro section for details).
As the moisture continues to move north, expect rain to fill in
over the area, so PoPs will be 70-80% overnight. With the
possibility for heavy rain over night, the flash flood watch will
remain in effect until 8am. Cloud cover will keep lows in the
lower 70s.

.Short Term [Tuesday Through Wednesday Night]...
A lot of uncertainty in the precip evolution through Tuesday as
the weak low over the east central Gulf lifts north towards the
Florida Big Bend. CAM guidance has had trouble picking up the
areas of heaviest precip (with today's round setting up over the
western Panhandle). Deep tropical moisture and difluent flow aloft
continue to argue for elevated PoPs through Tuesday, which is
supported by most of the guidance. While widespread heavy rain is
not anticipated, given the tropical nature of the convection, any
convective bands which setup and remain stationary could drop
several inches of rain in a very short amount of time. During the
day on Tuesday, expect best focus for rain to gradually lift
north, with best rain chances across the northwestern half of the
forecast area.

Rain chances will be on the decline for Wednesday. However, still
expect scattered showers and storms to develop with the upper
trough axis still west of the forecast area.

.Long Term [Thursday Through Monday]...
Expect to see decreasein PoPs during the latter half of the week
as the upper trough axis slides just east of the forecast area and
north to northwest upper level flow develops. Expect to see the
drier conditions continue throught he weekend with a cooler
airmass working in as well. Expect to see temperatures near or
just below normal for most of the area this weekend.

&&

.Aviation...
[Through 18Z Tuesday] MVFR ceilings will continue at all sites
through the period. Heaviest rain will be at DHN and ECP this
afternoon. Several pieces of guidance have ceilings dropping to
around 300 feet at sunrise. Included IFR starting around 12Z at
DHN, TLH and VLD.

&&

.Marine...
Winds over the coastal waters will increase overnight as weak low
pressure lifts north from the east central Gulf. Expect to see a
period of Small Craft Advisory conditions over the offshore
waters, with Exercise Caution over the nearshore legs. Winds and
seas will begin to diminish on Tuesday and remain below headline
levels through the end of the work week.

&&

.Fire Weather...
Hazardous fire weather conditions are not expected over the next
several days. Rain chances will start to decrease by mid-week.

&&

.Hydrology...
Over the past 24 hours, the rainfall amounts have generally been
confined to around 1.5 inches or less with some higher amounts
across the far western counties. With additional rainfall through
tomorrow night, total rainfall amounts through 8 AM Wednesday are
expected around 1 to 3 inches across SE Alabama and SW Georgia
with 2 to 5 inches expected across the Florida portion of the
CWA. However, isolated amounts up to 8 inches are possible.

With plenty of tropical mositure in place and the potential for
training of heavy rain leading to isolated higher rainfall totals,
flash flooding will be possible mainly in low lying and urban
areas. Given this, will continue with the Flash Flood Watch that
is in effect through tonight.

With the heaviest amounts predicted nearer to the coast, area
rivers will be able to handle this event without reaching flood
stage given the recent dry conditions. With current streamflows,
we'd need several inches of rain to get into the upper portions of
many of the larger rivers and streams to produce river flooding,
which still do not anticipate during this particular event.

&&

.Preliminary Point Temps/PoPs...

Tallahassee   73  87  74  87  71 /  80  60  20  40  20
Panama City   74  84  74  84  71 /  80  50  20  40  20
Dothan        70  84  70  84  67 /  80  60  30  50  20
Albany        71  84  72  85  68 /  80  70  30  50  30
Valdosta      71  86  73  86  70 /  80  70  30  50  20
Cross City    73  86  74  86  72 /  70  60  20  40  20
Apalachicola  74  85  75  84  72 /  80  50  20  40  20

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...FLASH FLOOD WATCH through Tuesday morning FOR Calhoun-Central
     Walton-Coastal Bay-Coastal Dixie-Coastal Franklin-Coastal
     Gulf-Coastal Jefferson-Coastal Taylor-Coastal Wakulla-
     Gadsden-Holmes-Inland Bay-Inland Dixie-Inland Franklin-
     Inland Gulf-Inland Jefferson-Inland Taylor-Inland Wakulla-
     Jackson-Lafayette-Leon-Liberty-Madison-North Walton-South
     Walton-Washington.

     HIGH RIP CURRENT RISK through Tuesday morning FOR Coastal Bay-
     Coastal Franklin-Coastal Gulf-South Walton.

GA...FLASH FLOOD WATCH through Tuesday morning FOR Brooks-Decatur-
     Grady-Lowndes-Seminole-Thomas.

AL...FLASH FLOOD WATCH through Tuesday morning FOR Geneva-Houston.

GM...SMALL CRAFT ADVISORY until 8 AM EDT Tuesday FOR Waters from
     Suwannee River to Apalachicola FL from 20 to 60 NM-Waters
     from Apalachicola to Destin FL from 20 to 60 NM.

&&

NEAR TERM...WESTON
SHORT TERM...CAMP
LONG TERM...CAMP
AVIATION...WESTON
MARINE...CAMP
FIRE WEATHER...HARRIGAN
HYDROLOGY...FIEUX