Severe Thunderstorm Warning 23, NWS Tallahassee, FL

Area Forecast Discussion
National Weather Service Tallahassee FL
1013 AM EST Fri Mar 1 2019

.UPDATE...

Raised PoPs this morning into early afternoon for ongoing
convection over the central and eastern portions of the CWA. No
other changes made. Occasional lightning and brief heavy downpours
expected as the line moves through.

&&

.PREV DISCUSSION [706 AM EST]...

.NEAR TERM [Through Today]...

The second in a series of shortwave troughs embedded in quasi-
zonal flow aloft is pushing across the Gulf Coast at this hour,
as evident on the latest IR and WV satellite imagery. An extensive
area of showers and a few embedded thunderstorms stretch from the
Florida Panhandle westward into eastern Louisiana at this hour.
Closer to the tri-state region, expect shower activity to persist
through daybreak, with additional showers and thunderstorms
developing later this morning into the afternoon. Given the warm,
moist airmass already in place, any pockets of heating will yield
sufficient instability to support thunderstorm activity given
increasing bulk shear values with the approach of the upper level
shortwave. Severe weather is not expected with this activity later
today. Temperatures will warm into the 70s this afternoon for
highs.

.SHORT TERM [Tonight Through Sunday Night]...

A series of weak upper level disturbances will traverse the area
through Saturday with the threat of scattered showers. A more
significant low pressure system and cold front will affect the
region late Sunday and Sunday night with a better chance of
widespread rain and perhaps some thunderstorms.

We'll have to watch for the potential for a few strong to locally
severe storms with the system late Sunday into Sunday night. Both
the 00z GFS and ECMWF move a 50-55 knot 850 mb jet across the
northern and western portions of the forecast area Sunday evening
into the overnight hours. Forecast SBCAPE values are actually
higher on the ECMWF than the GFS, likely because the overall
system is a bit strong on the ECMWF with a 1002 mb surface low
near Rome, GA Sunday evening. The ECMWF has SBCAPE over 600 j/kg
overlaid with 0-1 km helicity over 300 m2/s2 across the far
northwest portions of the area as the instability and shear are
co-located ahead of the front. A squall line will likely move from
the west-northwest to the east-southeast across the forecast area
Sunday evening and overnight. While gradual weakening will
probably occur as it moves deeper into the forecast area due to
dynamics and instability gradually decreasing with time, the line
may still be severe as it enters the northwest portions of the
forecast area. Given the amount of helicity, a couple of tornadoes
can't be ruled out along with the threat of straight line winds.

.LONG TERM [Monday Through Friday]...

The system on Sunday will exit the area rapidly on Monday with
drying behind it. The 00z ECMWF moves another weak shortwave
through briefly on Monday night into Tuesday morning with a
slight chance of a brief, light shower. However, most of the
middle of next week looks dry with an upper trough axis east of
the area and surface high pressure building northwest of us. By
late in the week, the pattern looks progressive with an upper
trough moving eastward from the western states and rain chances
perhaps returning around Friday. Temperatures will be on the cool
side behind the system on Sunday with lows dipping into the 30s
across a large portion of the area for Tuesday night and Wednesday
night. A light freeze is even possible across the northwest
portion of the area for Tuesday night.

.AVIATION...

[Through 12z Saturday] Areas of SHRA and isolated TSRA continue
to push across the region at this hour. Some areas of fog are also
expected through mid-morning in between the areas of showers.
Brief improvements to MVFR to VFR are expected this afternoon.
However, scattered TSRA are also expected to develop this
afternoon into the early evening.

.MARINE...

Fair boating conditions are forecast through Saturday. Increasing
winds and seas are expected for Sunday and Monday due to the
passage of a cold front. Winds and seas are expected to remain
elevated through mid-week with a colder air mass settling over the
waters.

.FIRE WEATHER...

Outside of potential low dispersions along the immediate north
Florida coastline this afternoon, hazardous fire weather
conditions are not expected through the next several days.

.HYDROLOGY...

A frontal boundary stalling near the region favors a wet pattern
over the next few days, culminating in a strong cold frontal
passage Sunday into Monday. Rainfall amounts of 1 to 2 inches are
possible across most of the area with the exception of the
southeast big bend, where lesser amounts are expected. Given that
it's been dry recently, significant flooding is not currently
expected with this system unless expected rainfall amounts
increase.

.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   76  61  78  62  79 /  80  20  40  10  20
Panama City   71  63  73  63  74 /  80  20  40  10  40
Dothan        73  59  74  62  78 /  60  20  30  20  50
Albany        73  59  74  61  78 /  70  20  30  20  50
Valdosta      74  61  77  61  79 /  70  20  40  10  20
Cross City    76  61  79  62  80 /  60  10  20  10  10
Apalachicola  71  63  73  64  73 /  80  20  30  10  20

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AL...None.
GM...None.
&&

UPDATE...Scholl
NEAR TERM...Pullin
SHORT TERM...DVD
LONG TERM...DVD
AVIATION...DVD
MARINE...DVD
FIRE WEATHER...Pullin
HYDROLOGY...DVD

Special Weather Statement
National Weather Service Tallahassee FL
809 AM EST FRI MAR 1 2019

FLZ011-016-GAZ156-011345-
Gadsden FL-Jackson FL-Decatur GA-
809 AM EST FRI MAR 1 2019

...SPECIAL WEATHER STATEMENT...

At 809 AM EST/709 AM CST/, Doppler radar was tracking a strong
thunderstorm near Chattahoochee, or 16 miles northeast of
Blountstown, moving northeast at 35 mph.

Half inch hail and winds up to 40 mph is possible with this storm.

Locations impacted include...
Quincy, Chattahoochee, Greensboro, Gretna, Douglas City, Mount
Pleasant, Hardin Heights, Rosedale, Recovery, Faceville, Hardaway,
Jinks, Sycamore, Quincy Airport and River Junction.

LAT...LON 3076 8451 3060 8451 3056 8488 3060 8488
      3060 8489 3061 8495 3066 8496 3085 8463
TIME...MOT...LOC 1309Z 245DEG 32KT 3061 8488

21-WD