Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tallahassee Florida
1000 am EST Thu Jan 29 2015
Near term [through today]...
surface high pressure situated along the southern Atlantic states
will slowly slide southeastward off the coast through the day. With
stacked weak high pressure aloft of the Gulf Coast, skies will stay
mostly clear. Highs today will be in the mid 60s.
[through 12z friday] VFR conditions will prevail through the
period with winds less than 10 knots generally from the south.
Prev discussion [344 am est]...
Short term [tonight through saturday]...
a dry cold front will move through the region overnight. Only an
increase in cloud cover is expected right ahead of the boundary.
Breezy northwest winds on Friday will bring in a drier and cooler
airmass. High temperatures will struggle to get out of the 50s
across the northern counties. With the high pressure area not
getting into the region until Saturday afternoon, winds will
remain strong enough overnight into Saturday to likely prevent
As the high pressure area moves off to the east, the moistening
trend will begin with southerly flow increasing late in the day on
Long term [saturday night through thursday]...
the next storm system will approach the area at the beginning of
the period. The models seem to be converging to a common solution
now of strong isentropic ascent ahead of the developing low
pressure area late Sunday afternoon generating an area of precip
followed by a band of showers and isolated thunderstorms on Sunday
night as the cold front sweeps through the forecast area.
Late Monday, the surface boundary will stall across the central
Gulf as an upper low back across southern baja ejects eastward
across Mexico and initiates surface cyclogenesis across the far
western Gulf on Tuesday. Its at this point that the GFS/Euro
diverge considerably. The 29/00z Euro indicates some degree of
phasing between the upper low over Mexico and an approaching
northern stream shortwave. This results in the upper low ejecting
further northward, pulling the attendant surface feature and
frontal zone further northward into our area. This pattern would
suggest a moderate to heavy rain threat for the area Tuesday night
Alternatively, the 29/00z GFS has less phasing between the
southern/northern stream mid and upper level features, thus the
next storm system stays largely to the south of the region,
tracking across the Florida Peninsula.
The Euro has been consistent in a more northern solution in the
last few runs, while the GFS has been Flipping back and forth.
Given this, have trended the forecast wetter at the tail end of
the extended, where what overlap there is favors increased rain
chances for the Florida counties.
winds will remain on the low side until Friday when they will
begin an increase to cautionary levels by Friday night. Winds will
diminish again late Saturday as high pressure moves near to the
marine area. The next storm system approaches on Sunday, resulting
in increasing southerly flow.
red flag conditions are not likely over the next several days.
the Ochlockonee River has crested through Concord this morning
with Havana likely to crest in the next 24 hours just above flood
stage. The Withlacoochee below Valdosta is still rising and will
likely crest around 18.5 feet early on Friday at the US-84 gage,
just below flood stage. Aside from the Havana and US-84 sites
being around flood stage, no further river flooding from last
week's rainfall is expected.
Streamflows remain above to well above normal across the entire
region. Overall rainfall from sunday's storm system shouldn't
exceed 1.5 inches across any particular basin, suggesting little
or no river flood threat. However, this rainfall will slow the
rate of recession across area river basins and possibly set the
stage for river flooding late next week should the heavier
rainfall solution with wednesday's storm materialize.
Preliminary point temps/pops...
Tallahassee 64 45 63 35 64 / 0 10 0 0 0
Panama City 62 50 60 39 59 / 0 10 0 0 0
Dothan 64 45 58 34 60 / 0 10 0 0 0
Albany 63 43 59 33 59 / 0 10 0 0 0
Valdosta 64 46 62 35 64 / 0 10 10 0 0
Cross City 66 44 66 36 66 / 0 10 10 0 0
Apalachicola 62 51 64 41 59 / 0 10 10 0 0