AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
910 PM EST Fri Jan 13 2012

NEAR TERM (Tonight)...
The back edge of the CIRRUS was rapidly pushing eastward across our
western zones at 02z and will be a non-factor on our minimum TEMPS.
The surface HIGH centered along the western Gulf coast this evening
will move little overnight. Thus, despite a very dry airmass in
place along with clearing skies, ideal radiational cooling
conditions will not occur. However, we are still expecting
unseasonably cold temperatures with inland areas dropping into the
MID to upper 20s. The only question continues to be whether some
locations experience a hard FREEZE (25 degrees or less for 2 or more
hours). Temperatures at 00z were already a FEW degrees below MOS
guidance where we are forecasting lows in the 25-26 degree RANGE.
This would encompass a large portion of the eastern Big bend. Will
be updated GRIDS and zones shortly along with issuing a Hard Freeze
WARNING for Jefferson, Madison, Inland Taylor, Lafayette and Inland
Dixie counties from 08z until 14z Saturday.

&&
SHORT TERM (Saturday through Sunday NIGHT)...The MEAN eastern
trough will be maintained through Saturday night as a pair of weak
shortwaves move through the base. While neither of these
shortwaves will push colder air in the region, they will serve to
slow the moderation of the airmass currently in place. After a
cold start tomorrow morning, high temperatures are forecast to
REACH the upper 50s by mid-afternoon. Another freeze will be
possible Sunday night as the surface high remains in a favorable
position for radiational cooling. Forecast temps are 4 to 5
degrees warmer than tonight with lows from 30 to 35 away from the
coast.

Heights will begin to rise on Sunday as the upper trough lifts
northeast and an upper ridge begins to build in from the west.
This will allow temperatures to continue moderating with highs in
the lower to mid 60s. Low temperatures should remain above
freezing Sunday night.

.LONG TERM (Monday through next Friday)...The large scale
longwave pattern commences fairly amplified. This is highlighted
in the NRN stream by weak troughing across WRN states and extreme
Wrn Atlc and ridging in between. SRN stream with weak troughing
PAC Coast to TX and ridging EWD into extreme Wrn Atlc. At surface,
high along NC/VA coast with ridge axis SWWD into Apalachee Bay.
Low in Canada N of MN with cold front Swwd into Colorado. This
place local area in very dry pattern.

During the rest of the period, Wrn upper trough digs Ewd while Srn
stream upper ridge moves offshore with Srn flow becoming nearly
zonal and stays so before weak troughing approaches shifting flow to
SWLY on Fri. Second upper trough over Gulf digs rapidly ESE Tuesday
and Tuesday night. At surface, Above troughs push surface low moves
to Srn Great Lakes kicking high into Atlc. Assocd cold front with
limited INSTABILITY dragged rapidly SEWD with deep SLY flow setup
from Gulf. GFS and ECMWF similar in timing and intensity of
front pushed THRU CWA Tues night exiting Wed morn ERN most zones
bringing SCT shwrs and a few tstms Tues AFTN into early Wed. In its
wake, strong high builds SEWD from Srn Plains Ewd spreading a
reinforcing shot of cold and very dry air across local region Wed
into Fri. By end of period high pushed offshore with next low moving
NEWD into TN valley dragging trailing cold front to Wrn Gulf. In
response, onshore flow with increasing chances of RAIN commences
again across local area by end of Fri.

Forecast will show Sct POPS Tues aftn into Wed. Otherwise NIL pops
thru period. Ahead of the front MIN temps will be around 10 degrees
above CLIMO Mon and Tues nights dropping to at or below climo Wed
and Thurs nights and may reach freezing in coldest locales. MAX
temps commence at least 10 degrees above climo on Tues dropping to
at or below climo on Wed then inching up to a few degrees above
climo by Fri. Average inland min/max temps are 39/62.