Severe Thunderstorm Warning 2, NWS Tallahassee, FL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TALLAHASSEE FL
257 PM EST SUN JAN 7 2007

.SYNOPSIS...LATEST ANALYSIS SHOWS A WARM FRONT WELL NORTH OF THE
AREA THAT EXTENDS EASTWARD FROM NORTHERN ALABAMA THROUGH GEORGIA
AND INTO THE CAROLINAS. THE COLD FRONT EXTENDS SOUTHWESTWARD FROM
NORTHERN MS/AL THROUGH LA AND INTO THE NORTHWESTERN GULF OF
MEXICO. A WEAK HIGH PRESSURE RIDGE AXIS EXTENDS WESTWARD FROM THE
CENTRAL ATLANTIC THROUGH THE FLORIDA PENINSULA AND INTO THE
EASTERN GULF OF MEXICO PROVIDING LIGHT TO MODERATE SOUTHERLY WINDS
OVER THE AREA.

&&

.SHORT TERM...(TONIGHT-TUESDAY NIGHT)
TONIGHT...LOW PRESSURE SYSTEM CENTERED OVER WESTERN TN WILL CONTINUE
TO DEEPEN AND INTENSIFY IN RESPONSE TO AN UPPER TROUGH THAT EXTENDS
SOUTHWARD THROUGH THE CENTRAL U.S AND BEYOND. THIS SYSTEM WILL
RAPIDLY MOVE NNE THROUGHOUT THE DAY AND WILL DRAG A COLD FRONT
ACROSS OUR AREA TONIGHT. SHOWERS AND THUNDERSTORMS ASSOCIATED WITH
THIS BOUNDARY SHOULD BEGIN FILTERING INTO THE WESTERN PORTIONS OF
OUR AREA THIS EVENING. MODELS CONTINUE TO BE IN AGREEMENT WITH THE
FRONTAL PASSAGE AROUND MONDAY MORNING. RAINFALL ACCUMULATIONS SHOULD
REMAIN AROUND A HALF INCH AND BELOW OVER THE MAJORITY OF THE AREA.
WEAK LAPSE RATES WILL GIVE WAY TO MARGINAL INSTABILITY VALUES AND AN
OVERALL LOW RISK FOR A SEVERE EVENT. HOWEVER SHEAR VALUES DO
SUPPORT THE DEVELOPMENT OF ROTATING STORMS.

MONDAY THROUGH TUESDAY NIGHT...SHORT WAVE WILL RAPIDLY ADVANCE NEWD
WITH THE SURFACE FRONT BEGINNING TO MOVE OFF THE ATLANTIC COAST
MONDAY EVENING. NW WINDS IN THE WAKE OF THE FRONT WILL BRING DRIER
AND COLDER CONDITIONS FOR THE REMAINDER OF THE PERIOD. FOR INLAND
AREAS...TUESDAY MORNING TEMPS WILL LIKELY REACH FREEZING FOR A BRIEF
PERIOD.

.LONG TERM...(WEDNESDAY-SUNDAY)
THE 00 UTC GFS AND ECMWF REMAIN IN GOOD AGREEMENT WITH THEIR
FORECASTS OF A DEEP UPPER LEVEL TROUGH DEVELOPING OVER THE WESTERN
PORTION OF THE COUNTRY...AND A CORRESPONDING STRONG RIDGE OVER THE
EAST. TEMPERATURES WILL START OFF ON THE COOL SIDE WEDNESDAY
MORNING...WITH ANOTHER CHANCE AT A LIGHT FREEZE IN THE FAVORED
LOCATIONS. A SLOW WARMING TREND WILL BEGIN ON THURSDAY AND LAST
THROUGH THE WEEKEND AS DEEP LAYER RIDGING DEVELOPS. THE GFS IS
EXHIBITING ITS USUAL PROPENSITY FOR MOISTENING THE LOW TO MID
TROPOSPHERE OVER MOST OF THE PLANET...AND THIS INFLUENCES THE MOS
POP (CAUSING IT TO BE 20-30 PERCENT FOR SEVERAL DAYS LATE IN THE
WEEK AND WEEKEND). WE PREFER THE ECMWF FORECAST OF A MUCH DRIER
TROPOSPHERE...ESPECIALLY GIVEN THE LOCATION AND STRENGTH OF THE DEEP
LAYER RIDGING. THUS ALL OUR POP IS BELOW 15 PERCENT.

&&

.AVIATION...LIFR/IIFR CIGS PERSIST AT PFN AND MVFR MARGINAL VFR AT
OTHER TERMINALS. EXPECT WITH INCREASING WQINDS...CIGS TO FINALLYL
IFT BY EARLY AFTERNOON. COLD FRONT WILL THEN COME IN FROM THE WEST
THIS EVENING AND OVERNIGHT. ALONG AND AHEAD OF THIS FRONT WILL BE
LOOKING FOR ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS. WESTERN
TERMINALS ARE MOST LIKELY TO SEE THIS ACTIVITY DURING THE FIRST HALF
OF THE NIGHT AND THEN EASTERN TERMINALS AFTER MIDNIGHT INTO THE
EARLY MORNING HOURS MONDAY. MVFR CIGS AND POSSIBLY VSBYS BUT WINDS
SHOULD LIMIT CHANCE FOR IFR CONDS. CLEARING THEN RAPIDLY COMES IN
MONDAY MORNING FROM THE NORTHWEST ON GUSTY WINDS WITH EXTENDED
PERIOD OF VFR CONDITIONS EXPECTED.

&&

.MARINE...WINDS AND SEAS SHOULD REMAIN BELOW CAUTION CRITERIA THROUGH
THE AFTERNOON. CAUTION WILL LIKELY BE REQUIRED BEGINNING SUNDAY
NIGHT WITH THE APPROACHING FRONT. DO NOT EXPECT CONDITIONS TO REACH
SCA CRITERIA AT THIS POINT FOR TONIGHT. FOR THE UPCOMING WEEK...HIGH
PRESSURE MOVES IN AND WINDS AND SEAS WILL REMAIN BELOW CAUTION
LEVELS.

&&

.FIRE WEATHER...CONDITIONS WILL APPROACH RED FLAG CRITERIA MONDAY
AFTERNOON AND TUESDAY AFTERNOON. WILL ISSUE A WATCH FOR TUESDAY
AFTERNOON.

&&

.PRELIMINARY POINT TEMPS/POPS...
TALLAHASSEE  55  66  32  62  31 /  70  30   0   0   0
PANAMA CITY  57  63  39  61  37 /  80  20  10   0  10
DOTHAN       51  62  34  59  31 /  90  20  10   0   0
ALBANY       54  61  34  60  32 /  80  30  10   0   0
VALDOSTA     57  63  34  60  32 /  60  30  10   0   0
CROSS CITY   60  67  34  62  29 /  50  50  10   0   0

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
AL...NONE.
GA...NONE.
FL...NONE.
GMZ...NONE.

&&

AVIATION/FIRE WEATHER...RB
REST OF DISCUSSION...AG
LONG TERM...FOURNIER