Severe Thunderstorm Warning 53, NWS Tallahassee, FL

Area Forecast Discussion
National Weather Service Tallahassee FL
131 AM EDT Sun Mar 16 2025

...New AVIATION...

.UPDATE...
Issued at 851 PM EDT Sat Mar 15 2025

There are no significant changes to the previous thinking below. A
significant severe weather event is still expected late tonight into
Sunday morning. Tornadoes, damaging wind gusts, and large hail are
all possible, including the potential for a few strong tornadoes
(EF2+). The highest probabilities are across the western portions of
the area, but there is at least some risk for the whole forecast
area. A tornado watch is in effect for the western portions of the
area, and this watch will probably be expanded eastward early Sunday
morning.

&&

.NEAR TERM...
(Through Sunday)
Issued at 357 PM EDT Sat Mar 15 2025

A significant severe weather outbreak is still expected from late
this evening into Sunday morning.

An energetic upper trough is making its way toward the Lower
Mississippi Valley right now. Severe thunderstorms are already
underway across MS, with a trailing line into southeast Louisiana.
The trailing line will be the part for us to watch as it moves
east tonight into an environment characterized by moderate
instability and high-end shear. The shear in the pre-storm
environment will be characterized by a southerly nocturnal low-
level jet of 50-65 knots, topped by 500 mb southwest flow of 60-80
knots. The southern end of the line is showing signs of being a
little capped, but this may serve to keep thunderstorms within the
line more supercellular. This would provide the storm-scale
organization needed to produce strong tornadoes and significant
damaging wind and hail. If the cap weakens some, then a more solid
line of thunderstorms would result. Either way, the environment
suggests a high-end severe event, especially along and west of the
U.S. 319 corridor. East of there, instability is a bit weaker, but
parameters still favor isolated severe storms east of 319.

Behind the squall line, a cold front will bring a turn to drier
westerly winds. Rapid clearing is expected late Sunday morning
into the afternoon.

&&

.SHORT TERM and LONG TERM...
(Sunday night through Saturday)
Issued at 357 PM EDT Sat Mar 15 2025

High pressure will build in on Sunday night and Monday. Surface
high pressure will move directly across the region on Monday night
and Tuesday.

The next cold frontal passage is expected on Wednesday night.
Moisture return will be limited in advance of this feature, so we
have kept low-chance showers but removed any mention of thunder
from the forecast.

The next surface high center will pass overhead on Thursday night
and Friday. No high-impact weather is expected from Sunday night
through next Saturday.

&&

.AVIATION...
(06Z TAFS)
Issued at 127 AM EDT Sun Mar 16 2025

Very windy conditions are ongoing across the area tonight with
gusty southerly winds and a strong low level jet bringing
additional low level wind shear to the region. A broken line of
showers and strong to severe thunderstorms is currently moving
into the area from the west and will push eastward through the
rest of the morning eventually impacting all taf sites. Conditions
improve to VFR afterward although breezy northwest to west winds
will remain.

&&

.MARINE...
Issued at 357 PM EDT Sat Mar 15 2025

Southerly breezes will steadily freshen through early Sunday
morning, with frequent gale force gusts developing west of
Apalachicola tonight. A squall line of severe thunderstorms will
pass the waters from late tonight through Sunday morning, bringing
high potential for severe winds, waterspouts, and possibly some
hail. Behind the squall line, a cold front will bring cross the
waters. Behind the front, a turn to westerly to northwesterly is
expected, with breezes becoming strong from Sunday night into
Monday. Winds will decrease on Monday, and a high pressure center
will pass across the waters on Tuesday. The next cold front will
cross the waters on Wednesday night.

&&

.FIRE WEATHER...
Issued at 357 PM EDT Sat Mar 15 2025

A cold front will cross the districts on Sunday
morning. In advance of the front, a severe thunderstorm squall
line will make steady progress across the districts tonight and
Sunday morning. Behind the front, rapid clearing is expected on
Sunday afternoon. A deep mixed layer on Sunday afternoon along
with somewhat strong transport winds will support pockets of high
dispersion. Winds will settle down somewhat on Monday, and a high
pressure center will pass directly across the districts on Monday
night and early Tuesday.

&&

.HYDROLOGY...
Issued at 357 PM EDT Sat Mar 15 2025

Isolated flash flooding is possible tonight and Sunday morning,
as a severe thunderstorm squall line moves eastward across the
region. The line will make steady progress eastward, limiting
duration of intense rainfall rates and therefore rainfall amounts.
Most places are forecast to get about 1-1.5 inches of rain, which
would generally not cause issues. However, if any parts of the
line temporarily slow down, then isolated flash flooding could
result.

Minor coastal flooding is possible along the shoreline of
Apalachee Bay on Saturday night and Sunday morning. Strong
southerly winds in advance of the Sunday cold front will push
water onshore, particularly along the north and northeast side of
Apalachee Bay. The normal tide cycle will be amplified this
weekend due to the recent full moon, so a lot will depend on if
the peak onshore push of water can overlap with the normal high
tide. For now, we are still good holding off on any coastal flood
headlines. At Saint Marks, for example, the peak onshore push of
wind and water will correspond with an intermediate (lower) high
tide. That would most likely keep the water level a couple tenths
of a foot below the criteria for minor coastal flooding. It could
be a close call along the northern portion of Apalachee Bay, but
not close enough yet for headlines. Bears watching.

&&

.SPOTTER INFORMATION STATEMENT...

Spotter activation is requested. Spotters should safely report
significant weather conditions and/or damage by calling the
office or tweeting us @NWSTallahassee.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   81  48  67  42 /  50   0   0   0
Panama City   75  49  67  45 /  10   0   0   0
Dothan        78  44  66  40 /   0   0   0   0
Albany        78  45  66  39 /  20   0   0   0
Valdosta      81  50  66  41 /  90   0   0   0
Cross City    76  50  68  40 /  90   0   0   0
Apalachicola  74  49  66  47 /  40   0   0   0

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...Wind Advisory until 5 AM EDT /4 AM CDT/ early this morning for
     FLZ007>017-026-027-108-112-114-115-127.

     High Rip Current Risk through Monday evening for FLZ108-112-114-
     115.

     High Surf Advisory until 5 PM EDT /4 PM CDT/ this afternoon for
     FLZ108-112-114.

GA...Wind Advisory until 5 AM EDT early this morning for GAZ120>131-
     142>146-155>158.

AL...Wind Advisory until 4 AM CDT early this morning for ALZ065>069.

GM...Small Craft Advisory until 4 PM EDT Monday for GMZ730-755-765-
     775.

     Gale Warning until 10 AM CDT this morning for GMZ750-752-770-772.

     Small Craft Advisory from 10 AM this morning to 3 PM CDT Monday
     for GMZ750-752-770-772.

&&

NEAR TERM...Haner
SHORT TERM...Haner
LONG TERM....Haner
AVIATION...Merrifield
MARINE...Haner
FIRE WEATHER...Haner
HYDROLOGY...Haner

Preliminary Local Storm Report
National Weather Service Tallahassee FL
1036 PM EDT Sat Mar 15 2025

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

1029 PM     Non-Tstm Wnd Gst Donalsonville           31.04N 84.88W
03/15/2025  M42 MPH          Seminole           GA   Mesonet

            An ambient weather station at Jimmy Drake -
            Donalsonville measured a gust of 42 mph.

&&

IG3