2013beach

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
504 AM EST Tue Jan 1 2013

.NEAR TERM [Through Tonight]…

Zonal flow will continue aloft as a mid/upper level shortwave
shears out over the Mississippi Valley today. As the flattening
trough moves into the Mississippi Valley it will slowly push a
cold front into the Southeast. With the slow approach of the
front, we will likely not see any rain across the area. If showers
happen to occur, they should remain confined to our SE Alabama and
western Panhandle counties later this afternoon. The main forecast
concern for today will be the development and evolution of low
clouds through the first part of the day. A mix of low and high
clouds will dominate the morning hours, followed by mainly upper
level clouds to finish the afternoon. Temperatures should be able
to climb to the 70 degree mark for most locations today.

Tonight, a weak impulse tracked back to the western Gulf Coast
will merge with the dampening low/mid level trough and result in a
brief period of amplification locally. This should develop a wave
of low pressure along the quasi-stationary front that will
traverse the Southeast through the night, before weakening over
the western Atlantic. The wave will bring the front into the Tri-
State region overnight resulting in showers across the
northwestern part of our forecast area. Lows will remain mild, in
the middle to upper 50s for most locations.

&&

.SHORT TERM [Wednesday Through Thursday]…

With little to no synoptic forcing expected on Wednesday the
aforementioned front will essentially be a stale boundary draped
across the local area. As a result, there will only be a slight
chance of rain for most spots through Wednesday afternoon. Ample
cloud cover will keep temperatures moderated in the lower 60s
south of the front, and possibly some 50s in the afternoon north
of the front.

Wednesday night, another weak southern stream impulse will combine
with favorable isentropic ascent and likely result in a rather
large rain shield spreading from southwest to northeast through
the day on Thursday. There is some uncertainty just how far north
the rain shield will extend, thus rainfall amounts remain highly
uncertain at this time. Should the plentiful rainfall occur far
enough north to favorably impact our region, event totals around an
inch to possible 2 inches in extreme cases, can be expected. On
the backside of the front (most of the area) high temps will climb
only to the middle and upper 50s. So any rain that falls will be a
rather cool rain.

&&

.LONG TERM [Thursday Night through next Tuesday]…

The extended period will begin with the last in the series of weak
low pressure waves exiting to our east, with another Ridge of High
Pressure building in for a fair and cool Friday. The first half of
Saturday looks to be fair and cool at this time as well, but yet
another wave of low pressure may try to return from the Gulf of
Mexico for later on Sat, lasting into Sunday and possibly Monday as
well, with the best chances for rain over the southern portion of
the CWA. Due to the uncertainty of the situation and significant
differences between the 00 UTC GFS (which would call for fair and
dry conditions with a slow moderating trend Sun-Tue), and the
earlier 12 UTC ECMWF (which would likely keep more unsettled
conditions across the area), will await the arrival of the 00 UTC
Euro before making the final call. The new 00 UTC ECMWF is in, and
little has changed. Therefore, will keep PoPs in the fcst through
Sunday Night.

&&

.AVIATION [Beginning 10Z Tuesday]…

Fairly tricky Taf fcst for most of the current package, as there are
a few pockets of MVFR level Cigs sliding in underneath the quickly
expanding Cirrus Deck. Expect at least a short period of these Cigs
at TLH, ECP, and DHN, while MVFR level Vis will remain possible at
ABY and VLD, which are out ahead of the lower clouds. During the
daylight hours Today, expect partly to mostly cloudy skies (at VFR
levels), before MVFR level Cigs return to the terminals after sunset
as the next Low Pressure system approaches from the west. Any rain
that falls should be light, but fcst PoPs are high enough to
include Prob30s at DHN, ECP, and ABY.

&&

.MARINE…

During the unsettled weather pattern outlined above, there will be
on-and-off periods of cautionary conditions over our Gulf Coast
waters. Advisory conditions should hold off, except for a brief
period on Friday as high pressure quickly builds in over the
waters.

&&

.FIRE WEATHER…

No fire weather concerns are expected for the next several days, as
an unsettled pattern will take a foothold over the region.

&&

.HYDROLOGY…

Minor river rises are possible Wednesday through Friday depending
on the exact location of the rain shield. At best, 1 to 2 inches
are expected, with isolated higher amounts (likely to occur nearer
to the coast) reaching 3 inches.