AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
338 PM EDT SAT Jul 14 2012

NEAR TERM [through Tonight]…
AS expected, CONVECTION has remained fairly suppressed today, with
the bulk of thunderstorms so far off to the east in parts of SW AL
and into MS. This is due to our local area being situated under an
upper level RIDGE axis. Therefore, some ISOLATED to SCATTERED storms
are expected to push off to the WNW at about 20kt for the remainder
of the afternoon and early evening before diminishing. Local
DOWNBURST parameters are not favoring much severe weather today, but
some of the stronger storms will probably produce some 30-40kt WIND
gusts (as has already been observed on EVX RADAR below 1000ft AGL” onClick=”return popup(this, ‘notes’)”>AGL in
several storms). No other significant changes were made in the short
term. Overnight convection should once again be concentrated
offshore and to the west of Apalachicola.

&&

.SHORT TERM [Sunday through Tuesday}…
Our region will remain in deep east-southeast FLOW on Sunday, as an
east-west oriented subtropical ridge continues to our north and
east. The drier AIR (mostly in the MID to upper TROPOSPHERE)
observed over our eastern zones today will cover much of our
forecast area Sunday, reducing the overall coverage of deep moist
convection. The greatest CHANCE for RAIN Sunday will be along and
south of the FL Panhandle coast Sunday morning, then over our N. FL
zones (around Cross City and Mayo) Sunday afternoon, as the FL east
coast sea breeze FRONT translates quickly westward. Some of these
showers and storms may REACH” onClick=”return popup(this, ‘notes’)”>REACH Tallahassee Sunday evening. Deep layer
MOISTURE will begin to recover Monday as a mid to upper tropospheric
TROUGH (currently well east of the FL Peninsula) approaches. This
will disrupt the 1000-700 MEAN wind, causing these steering currents
to become light and variable. Such a pattern often results in our FL
zones having the highest POP (40-50% in this case) as the FL Big
Bend/Panhandle sea breeze fronts take longer to propagate inland.
Good coverage of showers and thunderstorms is expected Tuesday
afternoon as the deep layer moisture (on the eastern side of the
aforementioned upper trough) continues to increase. Despite its
proximity, we still expect a fairly strong DIURNAL cycle to the
convection, with scattered storms over the coastal waters in the
morning, and inland during the afternoon and evening hours.
Temperatures will be near CLIMATOLOGY.

&&

.LONG TERM [Tuesday NIGHT through Saturday]…
The 00 UTC GFS and ECMWF have come into much better agreement on
this FCST cycle than last night`s, and it now appears that the GFS
has converged towards the more pessimistic Euro Solution. This
should equate to Higher POPS and Lower MAX TEMPS which are
reflected in the new GRIDS for this package, as the TUTT LOW,
which is now heading on a fairly expedient westward trek towards
the FL peninsula, gradually settles in the vicinity of the CWA
through Tuesday, before opening up into an Upper Level TROF. With
favorable onshore flow for Sea Breeze induced convection as well,
the pattern could very well end up even more disturbed than
advertised, and PoPs may need to be raised in the coming days if
the PROGGED pattern holds true and the models remain in good
agreement. By Saturday, Upper Level Ridging may begin to build in
from the east, which could at least lead to a temporary
improvement in the inclement Weather.

&&

.AVIATION…
[through 18z Sunday] We expect a predominately VFR period at all
terminals. The exception would be in any stronger TS or SHRA this
afternoon and early this evening, or if any low clouds were able to
form late tonight. For now, confidence was not HIGH enough in any
particular time frame for reduced flight categories to include in
this SET of TAFs. Any MVFR or IFR would LIKELY be isolated and not
last very long at any one location. Therefore, the OUTLOOK” onClick=”return popup(this, ‘notes’)”>OUTLOOK for
around the five terminals is for scattered MVFR/IFR in TSRA through
02-03z, and some patchy STRATUS or STRATOCUMULUS around 800-1500 FT
late tonight (10-13z).

&&

.MARINE…
Winds and SEAS have finally dropped below caution levels this
afternoon, but they will likely increase again late tonight and
early Sunday. However, this increase is not expected to be as strong
as what occurred early today, so exercise caution levels appear
unlikely. As the surface subtropical ridge shifts slowly south the
next FEW days, winds will become more southerly (as opposed to
easterly) by Monday.

&&

.FIRE WEATHER…
No critical fire weather conditions are expected with afternoon
minimum relative HUMIDITY at or above 40%.