Scientific Forecaster Discussion
fxus62 ktae 280031
afd forecast discussion
National Weather Service Tallahassee Florida
831 PM EDT Thu Jul 27 2017
Local radar imagery shows very isolated convection this evening,
mostly along our western border with mob/bmx. The 00z tae
sounding showed much drier air in place, and a peak at the lower
and mid level WV channels of GOES-16 shows this low-mid level dry
air extends across the majority of our forecast area. Adjusted
pops down over southwest Georgia based on this pattern, but nudged up
pops in southeast Alabama and the western Florida Panhandle. With northerly
flow, these isolated storms should move offshore over the next
Previous discussion [720 PM edt]...
Near term [through tonight]...
A surface low off the Georgia/Florida coast will continue to
influence rain chances this afternoon and evening. Showers and
thunderstorms with the low combined with the East Coast sea breeze
will keep the highest rain chances in the eastern third of the County Warning Area.
Pops will be 20-30% overnight with activity decreasing after
midnight. Lows tonight will be in the low to mid 70s away from the
Short term [friday through Saturday night]...
The weakness that has been situated over the area the past few
days will wash out as an upper low over the Great Lakes region
slides southeast. The surface low near the Ohio Valley on Friday
will slide to the mid-Atlantic on Saturday with a cold front
pushing across the southeast. Below normal pops are expected
Friday (20-30%) but the approaching front should help to enhance
convection on Saturday and thus will continue with above normal
pops for Saturday. A strong storm is possible on Saturday. The
front should move into/across the County Warning Area Saturday afternoon into
Saturday night. High temperatures will climb into the mid 90s
tomorrow, but will be limited to the upper 80s to low 90s on
Saturday with the additional cloud coverage and rain. Lows will be
in the low to mid 70s.
Long term [sunday through thursday]...
The European model (ecmwf) hangs the front that moves through late in the short
term across the County Warning Area into early next week while the 12z GFS pushes
it just south of the area. Given the time of year, most likely the
European model (ecmwf) solution is more realistic with moisture lingering across
the cwa, particularly the southern half instead of the front
clearing the area. This moisture will begin to lift northward
again mid to late next week with pops increasing again.
Aviation [through 00z saturday]...
Isolated convection this evening is unlikely to affect any taf
sites. In the early morning hours, there is a weak signal for MVFR
vsbys near vld, but with no rainfall there yet today to increase
soil moisture, left out of this taf package. Expect VFR conditions
through the period.
A cold front moving into the area Saturday into Saturday night will
help to increase winds and seas Friday and Saturday with exercise
caution winds possible on Saturday. Winds will subside to around
10 knots or less Sunday into next week. Showers and thunderstorms
will be possible each day, although the chances are more limited
for tomorrow, Friday.
Aside from high dispersions on Friday afternoon, due to elevated
winds, there are no hazardous fire weather conditions forecast for
the next several days.
A cold front will help to enhance typical summertime convection on
Saturday with the front lingering across the southern part of the
area into next week. Overall rainfall amounts of 2 inches or less
are expected through Tuesday morning, however isolated higher
amounts are possible. Widespread flooding is not expected given
amounts and timeframe, however localized ponding of water is
possible with typical heavy rain in the summertime convection.
Preliminary point temps/pops...
Tallahassee 73 94 75 90 74 / 30 30 10 50 50
Panama City 79 90 79 87 76 / 30 20 10 40 40
Dothan 4 88 70 / 30 20 20 60 20
Albany 74 95 76 87 71 / 20 20 20 60 20
Valdosta 72 93 75 90 72 / 30 40 10 60 50
Cross City 74 91 75 89 75 / 20 20 10 30 50
Apalachicola 76 91 79 90 77 / 30 20 10 30 50