Flash Flood Warning 14, NWS Tallahassee, FL

Area Forecast Discussion
National Weather Service Tallahassee FL
344 AM EDT Mon Aug 19 2019

.NEAR TERM [Through Today]...

A narrow upper trough will continue across the region today with a
weak surface trough as well. Deep tropical moisture will also remain
in place with precipitable water values over 2 inches. As a result,
a high coverage of showers and a few thunderstorms is expected
through the day today across the area. Some of the rain will be
heavy at times. The main issue is what to do with the flood watch
across the southeast big bend, either let it expire, extend it for
just those counties, or extend it and expand it northward? Guidance
indicates that the main focus for heavy rain today will be north of
the flood watch area across southwest and south-central Georgia.
However, there could still be a few bands of heavy rain that develop
across the southeast big bend through the morning hours before
activity tends to lift northward in the afternoon. As for areas
farther to the north, the flash flood guidance values are generally
3-4 inches in a 3-6 hour time period. Some of the storms today
appear capable of producing these amounts, but this will generally
be in small pockets rather than over a large area. Our local
ensemble of hi-res guidance indicates about a 20-30 percent chance
of exceeding flash flood guidance today across most of the forecast
area. Since the threat of flooding is expected to be localized
rather than widespread at this time, the preference is to not
blanket a large area with a watch. We will continue to monitor radar
trends and later guidance closely through the morning hours and make
a decision at the last minute on whether to extend and expand the
three county watch currently in effect through 8 am.

.SHORT TERM [Tonight Through Wednesday]...

Overall chances for showers and thunderstorms will come down
slightly from about 80% to 60%. The narrow upper level trough will
begin to weaken and slowly drift northeastward, allowing for
diminishing upper level enhancement of convection the next few days.
PW values of 2"+ are expected to continue across the area through
Tuesday. Then Tuesday night into Wednesday, slightly drier air (PW
of 1.5-2") will work its way into western portions of the area,
while the axis of deeper moisture shifts eastward into the eastern
FL Big Bend and NE FL. Highs will be in the upper 80s to low 90s and
lows will be in the low 70s.

.LONG TERM [Wednesday Night Through Monday]...

A more diurnal, seabreeze driven pattern will resume with a weak
pressure pattern in place at the lower and upper levels. Deeper
moisture (as seen in PW values increasing) will return to western
portions of the area on Thursday and remain in place into early next
week. As a result of the increase in moisture, PoPs will increase
again during the long term period. Highs will be mostly in the low
90s with lows in the low 70s.

&&

.AVIATION...
[Through 06Z Tuesday]

Low ceilings are expected to develop across the area this morning
with conditions ranging from MVFR to LIFR at times. The lowest
ceilings will lift during the mid-morning hours as showers and a
few thunderstorms develop across the area. Conditions will
fluctuate through the day as storms move across the area.

&&

.MARINE...

Winds around 10 to 15 knots today will fall overnight and remain low
for the rest of the week. Likewise, wave heights will fall to 2 feet
tonight and remain 2 feet or less for the rest of the week. Daily
chances for showers and thunderstorms will continue through the
period.

&&

.FIRE WEATHER...

Red flag conditions are not expected for the next several days with
relative humidity values remaining above critical levels.

&&

.HYDROLOGY...

As mentioned above, pockets of heavy rain will be the main threat
today across the area. Some localized areas of flash flooding are
possible. In addition, the Steinhatchee River is continuing a slow
rise. This basin will be near the southern edge of the bands of rain
this morning.

&&

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur by calling the office or tweeting us @NWSTallahassee.

&&

.PRELIMINARY POINT TEMPS/POPS...

Tallahassee   84  73  88  72  92 /  70  30  40  10  40
Panama City   85  75  87  75  89 /  70  30  40  20  40
Dothan        89  72  88  71  90 /  70  40  60  30  50
Albany        86  73  87  73  91 /  70  50  60  30  50
Valdosta      83  72  87  72  91 /  80  20  30  20  40
Cross City    84  72  91  73  91 /  60  10  20  30  50
Apalachicola  84  76  87  75  88 /  80  30  30  10  30

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...Flood Watch until 8 AM EDT this morning for Coastal Dixie-
     Coastal Taylor-Inland Dixie-Inland Taylor-Lafayette.

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

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

NEAR TERM...DVD
SHORT TERM...Nguyen
LONG TERM...Nguyen
AVIATION...DVD
MARINE...Nguyen
FIRE WEATHER...DVD
HYDROLOGY...DVD

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1247 AM EDT MON AUG 19 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1245 AM     HEAVY RAIN       SUWANNEE                29.33N 83.14W
08/19/2019  M17.36 INCH      DIXIE              FL   MESONET

            4 DAY STORM TOTAL OF 17.36 INCHES AT
            WUNDERGROUND SITE KFLSUWAN3.

1245 AM     HEAVY RAIN       HORSESHOE BEACH         29.45N 83.29W
08/19/2019  M15.85 INCH      DIXIE              FL   MESONET

            4 DAY STORM TOTAL OF 15.85 INCHES AT
            WUNDERGROUND SITE KFLHORSE10.

1245 AM     HEAVY RAIN       1 S STEINHATCHEE        29.66N 83.39W
08/19/2019  M30.15 INCH      DIXIE              FL   MESONET

            4 DAY STORM TOTAL OF 30.15 INCHES AT
            WUNDERGROUND SITE KFLSTEIN5.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
159 AM EDT MON AUG 19 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1256 AM     HEAVY RAIN       4 SE TYNDALL AFB        30.03N 85.53W
08/19/2019  M6.31 INCH       BAY                FL   AWOS

            6.31 INCHES OF RAIN MEASURED IN 4 HOURS AT
            THE TYNDALL DRONE RUNWAY KTDR.

&&

DVD