Severe Thunderstorm Warning 387, NWS Tallahassee, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1034 AM EDT THU AUG 6 2015

.Near Term [Through Today]...

A 12Z regional surface analysis showed low pressure along the
southern Illinois-Indiana border with a cold front extending
southwestward from it roughly along the Mississippi River through
Memphis, then diagonally across Arkansas. A warm front also extends
eastward from this low, analyzed to arc around northern Kentucky and
southern West Virginia then along the North Carolina-Virginia
border. Southeast of this low lies a stationary boundary from about
Biloxi, MS to Swainsboro, GA. Convection started early this morning
along and south of this boundary and a localized area of low
pressure appears to have developed near Cordele, GA. These storms
have generally been moving parallel to the boundary, or southwest to
northeast. By this afternoon, most of the convective activity is
expected to be focused over our northern zones.

The 12Z TAE sounding showed a PW of 2.12", which is well above
normal with 0-6 km steering flow from the southwest which will
continue to keep Gulf moisture in place over the area today. Mid
level lapse rates were around 6 C/km, which is quite unstable
considering how moist the profile is, and SBCAPE was around 1700
J/kg which has already begun to increase to around 2000 J/kg
according to the SPC mesoanalysis page and will continue to increase
into the afternoon. With this instability in place, some of the
storms today are expected to become strong enough to produce
downbursts of damaging winds. Due to the early start to convection
across the area, highs will be around 90.

&&

.Aviation...

[Through 12Z Friday] Outside of convection, VFR conditions are
expected to prevail. Afternoon convection appears to be most likely
near DHN and ABY.

&&

.Prev Discussion [326 AM EDT]...

.Short Term [Tonight Through Saturday]...
With the main shortwave, associated with the deepening upper
trough, crossing the forecast area during the overnight hours,
showers and thunderstorms may linger longer than usual this
evening, especially over the northern portion of the forecast
area.

For Friday, while the shortwave will exit to the east, the
associated surface front will sag southward into SE Alabama and
SW Georgia by afternoon. Stronger than normal mid-level
northwesterly flow (30 knots at 500mb) combined with relatively
strong westerly to southwesterly low-level flow and plenty of
instability will support some stronger storms Friday afternoon
into the evening. Best chances for severe storms currently
expected to be across South Central Georgia into the Florida Big
Bend. Damaging straight line winds will be the primary threat with
these storms, although some large hail cannot be ruled out. SPC
has maintained a Marginal Risk for Friday.

There is some disagreement among the guidance for Saturday on how
much dry air works its way into the forecast area. The GFS
substantially drier with limited support for convection. The
ECMWF is not as dry, although it has trended drier from its
previous few runs. Given the GFS and trend of the ECMWF, have
lowered PoPs somewhat for Saturday, with best rain chances over
the coastal waters and the eastern Big Bend. The lower rain
chances and low-level northerly flow will allow temperatures to
heat back up, with highs pushing back into the mid 90s.

.Long Term [Saturday Night Through Thursday]...
Northerly flow will continue on Sunday into Monday with a big
ridge holding in place over Texas. This should help to confine the
best rain chances closer to the coast. The upper trough along the
east coast will begin to amplify again by Tuesday with rain chance
increasing through the middle of next week. Above normal
temperatures are on tap for Sunday and Monday, before returning to
more seasonal levels by mid week.

.Marine...
A front approaching from the north will tighten the pressure
gradient over the waters into Friday with increasing west to
southwest flow. Conditions will likely reach exercise caution
levels by late tonight with marginal advisory conditions by Friday
afternoon. Conditions will improve by Saturday into early next
week as the gradient weakens.

.Fire Weather...
Hazardous fire weather conditions are not expected over the next
several days.

.Hydrology...
The Steinhatchee River continues to slowly fall. It is expected
that the river will remain above flood stage through at least
Friday morning.

With mainly scattered afternoon and evening storms the next few
days, do not anticipate any additional river flood concerns.
However, areas in the Southeast Florida Big Bend, particularly in
Dixie County, will be especially prone to further areal flooding,
should any storms move over the area during the next couple of
days.

&&

.Preliminary Point Temps/PoPs...

Tallahassee   92  76  92  76  96 /  50  20  50  30  30
Panama City   87  80  89  79  91 /  30  30  40  30  30
Dothan        91  75  93  74  95 /  60  40  40  20  30
Albany        91  75  92  74  94 /  70  50  50  20  20
Valdosta      91  75  92  73  94 /  50  30  50  20  30
Cross City    90  76  89  76  92 /  20  20  50  40  40
Apalachicola  89  79  90  79  92 /  30  20  40  30  30

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...HIGH RIP CURRENT RISK through late tonight FOR Coastal Bay-
     Coastal Gulf-South Walton.

GA...NONE.
AL...NONE.
GM...NONE.
&&

NEAR TERM...MOORE
SHORT TERM...CAMP
LONG TERM...CAMP
AVIATION...MOORE
MARINE...CAMP
FIRE WEATHER...DVD
HYDROLOGY...CAMP

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
1055 AM EDT THU AUG 06 2015

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

1045 AM     LIGHTNING        1 N ARP                 31.77N 83.41W
08/06/2015                   BEN HILL           GA   TRAINED SPOTTER

            *** 1 INJ *** LIGHTNING STRUCK A TREE LIMB THAT THEN FELL
            THROUGH A ROOF AND STRUCK A WOMAN IN THE FACE.

&&

WOOL