FXUS62 KCAE 041138
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
638 AM EST FRI DEC 4 2009
.SYNOPSIS...
LOW PRESSURE WILL DEVELOP ALONG A STALLED FRONTAL BOUNDARY TO OUR
SOUTH TONIGHT AND SATURDAY...SPREADING MOISTURE INTO OUR REGION.
HIGH PRESSURE WILL BUILD IN SUNDAY. AN ACTIVE JET STREAM WILL LEAD
TO LIGHT RAIN POTENTIAL MONDAY AND TUESDAY. A COLD FRONT IS EXPECTED
TO MOVE THROUGH WEDNESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
CURRENT SURFACE ANALYSIS INDICATES FRONT STRETCHED WELL TO OUR
SOUTH...WITH HIGH PRESSURE CENTER WELL TO OUR NW. UPPER TROUGH
EXTENDS FROM THE GREAT LAKES SW INTO THE FOUR CORNERS REGION.
RELATIVELY DRY AIR WILL REMAIN IN PLACE TODAY. A STRONG SW UPPER
FLOW OVER OUR REGION WILL LEAD TO INCREASING HIGH TO MID LEVEL
CLOUDINESS PUSHING INTO OUR REGION.
&&
.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
MODELS INDICATE MAIN UPPER TROUGH ENERGY TO SWING AROUND TO
THE MISS VALLEY BY TONIGHT...AND INDICATE A PAIR OF WEAK LOWS
DEVELOPING ALONG THE FRONT OVER THE GULF AND ATLANTIC. LATEST MODEL
RUNS ARE INDICATING GULF LOW TO REMAIN WEAK WHILE THE ATLANTIC LOW
WILL DEVELOP AND MOVE NE. THIS APPEARS TO KEEP THE BEST MOISTURE
TRANSPORT MAINLY TO OUR EAST...WITH PERHAPS UPPER LIFT PROVIDING
THE MAIN MECHANISM FOR ANY PRECIPITATION OVER OUR FORECAST AREA
(FA). LATEST MODEL RUNS ARE NOW TRENDING DOWN ON POP AND QPF FOR
OUR FA. SINCE MODELS ARE SHOWING SOME RUN TO RUN
INCONSISTENCY...CONFIDENCE ON SPECIFICS IS REDUCED AND WILL ONLY
TWEAK POPS DOWN A TAD...GENERALLY BLENDING ONGOING FORECAST WITH
MOS CONSENSUS ON POPS. IT STILL DOES NOT APPEAR THAT WE WILL HAVE
PRECIPITATION TYPE CONCERNS IN OUR FA. SUFFICIENTLY COLD AIR WILL
NOT BE IN PLACE AHEAD OF TIME. SOIL TEMPS ARE STILL QUITE
HIGH...AND EARLY DECEMBER IS A LITTLE EARLY CLIMATOLOGY WISE FOR
WINTER PRECIP. ARRAY OF DATA INCLUDING FORECAST SOUNDINGS AND
PARTIAL THICKNESS NOMOGRAM ALL POINT TO JUST LIQUID RAIN FOR OUR
FA.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
GFS/ECMWF CONTINUE TO INDICATE SURFACE HIGH PRESSURE BUILDING IN
SUNDAY. LATEST RUNS INDICATE REDEVELOPING STRONG SW UPPER FLOW AND
EMBEDDED IMPULSES...WITH WEAK ISENTROPIC LIFT AND LIGHT PRECIP
POTENTIAL RETURNING PERHAPS AS EARLY AS SUNDAY NIGHT...CONTINUING
UNTIL A FRONT MOVES THROUGH LATE WEDNESDAY.
&&
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL COVER THE REGION TODAY. LOW PRESSURE WILL
DEVELOP IN THE GULF OF MEXICO LATE TODAY AND SPREAD RAIN INTO THE
AREA LATE TONIGHT AND SATURDAY. VFR CONDITIONS TO BEGIN 24 HOUR
PERIOD WILL LOWER TO MVFR 02Z-04Z THIS EVENING AND BECOME IFR
06Z-08Z TIME FRAME AS RAIN MOVES INTO TAF SITES.
EXTENDED OUTLOOK...IFR CONDITIONS SATURDAY THEN VFR SUNDAY AND
MONDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...07
