Area Forecast Discussion
Issued by NWS
FXUS62 KTAE 130042
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
842 PM EDT Wed Jun 12 2013
.NEAR TERM [Through Tonight]...
Isolated storms from earlier in the evening have ceased and no
more precipitation is expected overnight. Lows tonight will be in
the mid 70s, with high humidities present. Other than a few minor
tweaks to the temperature grids, the previous forecast remains on
.SHORT TERM [Thursday Through Friday Night]...
Despite the upper level ridging over the U.S. which has been
keeping the weather hot and dry (with the exception of afternoon
sea-breeze showers and thunderstorms near the coast), the pattern
gets a little more interesting as a short wave trof digs down the
east side of the ridge. The shortwave trof will enhance surface
pressure drops and upper level winds (and thus shear). A line of
showers and thunderstorms along a weak frontal boundary from the
surface low is expected to dip into our area Thursday night. There
is some model disagreement as to whether or not these storms will
dip as far south as our forecast area, but if they do the model
MLCAPE values of around 3000 J/kg and 0-6 km bulk shear of around
30 kts suggest that they will be strong to severe storms. SPC has
our AL and GA counties in a slight risk for severe thunderstorms
in the day 2 outlook. The bulk shear is a little low for supercell
development, but stronger individual cells may form along the
line, especially with such a high amount of instability. Looking
at the Fri 00Z model soundings, there are conditionally unstable
lapse rates through most of the profile and drier air has made its
way in the mid levels thanks to the high pressure we`ve been
under. CAPE contribution in the -10 to -30 C range is around 1000
J/kg and DCAPE is 1500-2000 J/kg. These parameters suggest that
there is a threat for both severe winds (58+ MPH) and 1" hail.
Lower level vorticity and wind shear is higher to the north of our
area, but a tornado from a stronger cell can`t be ruled out
Highs tomorrow will be in the upper 90s, similar to today, but may
be a little lower Thursday depending on the cloudiness ahead of the
line of storms and the timing of the storms themselves. Lows
Thursday night will be in the low-mid 70s, a little warmer due to
higher cloud cover and rain chances, but return to the lower 70s
.LONG TERM [Saturday through Tuesday]...
After the potential system passes Thursday night, high pressure
aloft and at the surface will build eastward and be the main
synoptic scale influence on the forecast area`s weather through
Tuesday. On Tuesday, another shortwave will propagate through the
upper level ridge and set up a pattern similar to Thursday night
(see short term). Highest PoPs in the forecast period are Tuesday
and Wednesday. Expecting highs in the 90s and lows in the low 70s
through the long term period.
[Through 00Z Friday] VFR conditions are expected throughout the
entire period for all terminals. There is a slight chance for TSRA
tomorrow after 18Z at KTLH and KVLD, but because PoPs are low this
was left out of the TAF package.
A low pressure system to our northwest will dip ito the SE US and
increase chances of showers and thunderstorms Thursday night and
Friday. Although most of the storms will be inland, some stronger
storms are expected, so there is the possibility of brief periods
of cautionary to advisory winds as these storms pass through.
Otherwise, winds and seas will remain below headline criteria
through the period.
Red Flag conditions are not expected for the remainder of the work
week. Dispersion values may climb above 75 Thursday afternoon, from
a combination of strong vertical mixing and increasing winds aloft.
The Ochlockonee River at Thomasville is in action stage and may
rise slightly with rain tomorrow night, but it is not expected to
reach minor flood stage. MMEFS shows no sites are forecast to
reach flood stage in the near future. Although there is potential
for some severe thunderstorms Thursday night, WPC QPF for our area
is 0.25" or less and is not expected to cause significant rises on
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 73 96 75 95 72 / 10 20 20 30 10
Panama City 76 91 78 92 76 / 10 10 20 20 10
Dothan 75 99 74 95 71 / 10 10 30 10 0
Albany 75 99 74 93 69 / 10 10 40 10 0
Valdosta 73 97 74 93 70 / 10 20 30 30 10
Cross City 72 92 73 92 71 / 10 20 20 30 20
Apalachicola 76 89 77 91 75 / 10 10 20 30 10