AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
520 AM EDT Fri Jul 13 2012



NEAR TERM [Through Tonight]...
Upper RIDGE extending down the Eastern Seaboard from the MID-
Atlantic will continue to push westward and nudge the persistent
TROUGH/upper LOW that has plagued the Southeast west into LA and TX.
At the surface, we will continue to reside on the southwestern
periphery of the subtropical ridge, under an east/southeasterly
FLOW regime.

This morning, showers and thunderstorms have formed offshore along
the convergent zone ahead of the remnant East Coast Seabreeze
FRONT. A FEW showers have been able to survive along this boundary
across land areas, but have been rather feeble. AS the storms
across our Big Bend waters move west towards the coast, the
possibility of waterspouts exists. This is especially true along
the Franklin and Gulf county coastlines.

This afternoon will be very similar to yesterday with the easterly
flow creating enhanced CONVERGENCE along the Panhandle Seabreeze
front and across the Forgotten Coast. Later in the afternoon, the
East Coast Seabreeze front will REACH" onClick="return popup(this, 'notes')">REACH our easternmost counties
bringing an enhanced risk for showers and thunderstorms. With
precipitable water values well above average for this time of
YEAR (~+2 standard deviations), have gone with higher than CLIMO
POPS for one more afternoon.

The severe weather threat for this afternoon appears to be very
low. Lower than average INSTABILITY coupled with poor lapse rates,
small SFC/mid level THETA-E differences, and near typical 500 MB
temperatures would suggest a near zero CHANCE for severe
downbursts and/or HAIL. However, there certainly exists the
possibility of some sub-severe downdrafts taking a tree or two
down in the strongest storms.

Tonight will be much like last NIGHT as well. Expect showers to
gradually diminish over land, with much more activity across
Apalachee Bay with the passage of the East Coast Seabreeze.
&&

.SHORT TERM [Saturday Through Sunday]...
The upper ridge will take a much more firm hold of the Southeast
on Saturday and Sunday. This will result in a much drier AIR mass,
with the seabreeze fronts continuing to dominate the afternoon
weather pattern. Will keep PoPs at or below climo through the
remainder of the short term, taking into account the dry air.
Temperatures will hold in the lower to mid 90s inland each
afternoon, with temperatures along the coast remaining in the
middle to upper 80s.
&&

.LONG TERM [Sunday Night through Friday]...
There are some generally minor to moderate discrepancies between
the the 00 UTC GFS and ECMWF runs through much of the extended
period, with the GFS favoring Upper Level Ridging over the SE U.S.
and a Sfc Ridge over the Northern Gulf, while the Euro has weaker
Upper Ridging displaced off to our NW, with a weakness in the
Pattern Aloft which gradually slides down to our CWA from the NE
over time. The ECMWF also favors somewhat weaker Sfc Ridging over
the Gulf, with a slightly stronger Bermuda HIGH (which will have
to first displace an ACTIVE TUTT Low to verify). While both
solutions favor onshore low level flow (which is generally
favorable for fairly high Sea Breeze induced PoPs this time of
year), we leaned more towards the GFS solution in which the Upper
Ridging would suppress PoPs a bit below Climo and Sea Breeze Climo
levels, and also allow for above NORMAL TEMPS with Highs in the
Mid 90s away from the Coast.
&&

.AVIATION...
Despite the Fairly WIDESPREAD PoPs across the Region on Thursday,
the terminals have remained at VFR levels so far for tonight.
However, since it is only 5 AM EDT at this time, and there was a
decent amount of lingering low level cloudiness through close to 4
AM, there is still time for a few of the sites to drop down to
MVFR levels, especially at VLD and possibly ECP which received
over 1 inch of RAINFALL today. Otherwise, expect another active
day of CONVECTION, with PoPs in the 40-60% RANGE at most of the
terminals.
&&

.MARINE...
Winds and SEAS will remain relatively low under the influence of
high PRESSURE. Afternoon enhancements are expected near the coast
each afternoon, with evening enhancements LIKELY along the East
Coast Seabreeze each night. Even in times of enhanced winds and
seas, expect winds below 15 knots and seas below 3 feet.
&&

.FIRE WEATHER...
Plenty of Low Level MOISTURE will keep Afternoon Relative Humidities
safely above Red Flag Levels during the next few days, despite the
lower PoPs on Saturday and Sunday compared to today.