Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Tallahassee Florida
850 PM EDT Mon Sep 1 2014
Near term [through tonight]...
The 7 PM EDT regional surface analysis showed the western
extension of the Bermuda ridge from central Florida to coastal MS, except
for a weak, north-south oriented trough along the western Florida
Peninsula. There was also a weak, east-west oriented trough across
central Georgia and Alabama. Vapor imagery and upper air data showed a
rather small, flat anticyclone centered over southeast Georgia. Most of
the showers & thunderstorms this evening were located near the
aforementioned troughs, but we expect some of these storms to
affect the eastern portions of our forecast area- mainly east of
Tallahassee. As has been the case the past few nights, and it's
forecast by several of the latest convection allowing models
(cams), showers & storms may linger longer than normal for
summertime, finally dissipating shortly after midnight.
[through 00z wednesday]...vld and aby will be the only terminals
with a lingering threat for showers and thunderstorms this
evening. By midnight, all terminals should be VFR with no threat
for storms or restrictions. Tomorrow afternoon will feature
another scattering of storms, though the terminals with the
highest chances of being impacted will be ecp and vld.
Prev discussion [331 PM edt]...
Short term [tuesday through Wednesday night]...
A slowly weakening 594 dm upper level ridge (which is currently
centered over the cwa) will continue to dominate the synoptic
pattern over the region as it slowly slides to the west. However,
there is still plenty of deep layer moisture under this ridge, which
when combined with very weak low level flow will keep pops generally
in the 30-50% range both Tuesday and Wednesday, with most of the
convective forcing generated by the sea breeze circulation.
Afternoon temps will remain on the hot side as well, with highs
still in the mid to upper 90s away from the coast. Overnight lows
will continue to range from the lower to middle 70s inland to the
middle to upper 70s near the coast.
Long term [thursday through monday]...
Although the synoptic pattern will be dominated by weak upper level
ridging throughout most of the extended period, the positioning of
the Bermuda high pressure system at the surface will still allow for
an ample supply of deep layer moisture to advect in from the
southeast. Additionally, the upper ridge is expected to weaken and
retrograde westward over time, which should trend daytime pops at or
even above climo levels (generally in the 30-50% range). While high
and low temps are not expected to be nearly as warm as they have
recently been, they should still average above climo, with highs
generally in the lower to a few middle 90s, with lows still in the
lower to middle 70s.
A very weak surface pressure pattern will dominate the coastal
waters for the next several days, allowing the diurnal sea breeze
circulation to govern the predominantly light winds. Seas that have
been slightly elevated by a long southeasterly fetch during the past
couple of days will diminish as well.
Afternoon relative humidity values will remain well above critical
levels, so red flag conditions are not expected through this week.
Rivers in Georgia/Alabama remain very low, with a few points
potentially reaching record low levels in the next couple of weeks
if the unusually dry conditions continue. Rivers are not quite as
low in Florida, though with little or no significant rainfall
expected this week, the downward trend should continue.
Preliminary point temps/pops...
Tallahassee 74 96 73 96 73 / 10 30 30 40 20
Panama City 77 92 77 92 78 / 10 30 20 30 20
Dothan 73 98 73 96 73 / 20 20 20 40 20
Albany 74 97 73 97 73 / 30 30 20 40 20
Valdosta 73 96 72 96 71 / 40 40 30 40 20
Cross City 73 94 71 94 71 / 30 40 30 40 20
Apalachicola 76 90 77 90 77 / 10 30 20 30 20