Severe Thunderstorm Warning 133, NWS Tallahassee, FL

Area Forecast Discussion
National Weather Service Tallahassee FL
332 PM EDT SAT JUN 11 2016

.NEAR TERM [Through Tonight]...

Convective development appears to be trending as expected this
afternoon and that is providing some temperature relief, at least
for the southwestern half of the forecast area. After 00Z, we look
for convection to linger over our western and southeastern zones
where we have a 20-30% PoP. Lows tonight will be in the lower to mid
70s.

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

The mean deep layer flow through Monday will be from the NW, with a
500 mb ridge axis situated over the central CONUS. At the surface,
an east-west oriented ridge along the Gulf Coast will shift
southward as a cold front approaches from the north. However, the
main thrust of cooler, drier air will be to the southeast, and
this front will stall across southeast and central GA early
Monday. The latest suite of NWP guidance forecasts little if any
Q-G forcing during this period, so the diurnal sea breeze
circulation will be the primary driving force for precipitation.

With the expected offshore component to the 1000-700 mb mean winds,
the FL Panhandle and Big Bend sea breeze fronts will be slower to
develop and move inland, meaning a later start to afternoon
storms. In fact, for Sunday several of the CAMs indicate that the
sea breeze front may get pinned at the coast for much of the afternoon,
with PoPs only around 30% in our FL and AL zones (and less that
20% elsewhere). On Monday we expect the NW winds to weaken some,
allowing for a more even distribution of PoPs (30-40%). The
forecast relatively high dewpoints (lower to mid 70s) mean that
there will be a substantial cumulus cloud field, which should
prevent high temperatures from exceeding the mid 90s. However,
this comes at the coast of less favorable evaporative cooling
conditions, and daytime heat index values will climb above 100 F.

.LONG TERM [Tuesday Through Saturday]...

While much of the CONUS will be under the influence of a broad upper-
level ridge centered over the Central Plains, our forecast area will
be under the influence of a weak trough just to our west, that
will get cut off from the westerlies. A more substantial long
wave trough will develop over much of the eastern CONUS by next
weekend. For much of this workweek the presence of the upper level
trough will help promote a favorable thermodynamic environment for
afternoon and evening deep moist convection. Daytime PoPs will be
above climatology, at least 50%. The increase in clouds will keep
highs near average, around 90, though the high humidity will make
it feel warmer. Lows will be slightly above average, in the lower
to mid 70s.

&&

.AVIATION [Through 18Z Sunday]...

VFR conditions are forecast to prevail through this evening outside
of thunderstorms. We now show visibility restrictions to MVFR
during the predawn hours at TLH and VLD. Convection should get
started around 15-16Z on Sunday and may already be in the vicinity
of ECP by that time.

&&

.MARINE...

Winds will generally be fairly light from a westerly direction as a
surface ridge becomes centered south of the coastal waters. Winds at
night will be 10 kt or less, then 10 to 15 kt near the coast during
the afternoon and early evening hours.

&&

.FIRE WEATHER...

There are no fire weather concerns.

&&

.HYDROLOGY...

Locally heavy rains over the next several days could cause localized
flooding of low-lying, poor drainage areas, especially in urban
areas. However, we do not expect enough widespread heavy rain to
cause significant rises on the local river system.

&&

.PRELIMINARY POINT TEMPS/POPS...

Tallahassee   74  93  75  95  75 /  10  30  10  40  20
Panama City   77  86  78  87  77 /  20  20  10  30  10
Dothan        74  93  74  94  75 /  20  40  20  40  30
Albany        73  94  74  96  75 /  10  20  20  30  30
Valdosta      72  93  73  95  74 /  10  20  10  40  30
Cross City    73  91  74  93  76 /  30  30  10  20  20
Apalachicola  76  87  77  89  77 /  20  20  10  10  10

&&

.TAE WATCHES/WARNINGS/ADVISORIES...

FL...None.
GA...None.
AL...None.
GM...None.

&&

NEAR TERM...Wool
SHORT TERM...Fournier
LONG TERM...Fournier
AVIATION...Wool
MARINE...Fournier
FIRE WEATHER...Moore
HYDROLOGY...Fournier