FXUS62 KCAE 282321
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
621 PM EST SAT NOV 28 2009
.SYNOPSIS...
DRY HIGH PRESSURE WILL BE CENTERED NEAR THE FORECAST AREA THROUGH
SUNDAY. AS APPROACHING COLD FRONT WILL MOVE THROUGH THE FORECAST
AREA MONDAY AFTERNOON AND EVENING. LOW PRESSURE FROM THE GULF OF
MEXICO WILL MOVE INTO THE AREA WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
HIGH PRESSURE WILL BE CENTERED NEAR THE FORECAST AREA. EXPECT STRONG
RADIATIONAL COOLING ALTHOUGH IT WILL BE LIMITED SOMEWHAT BY
UPPER-LEVEL CLOUDINESS. USED THE COOLER TEMPERATURE GUIDANCE BECAUSE
OF THE RADIATIONAL COOLING.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
MILDER TEMPERATURES WILL OCCUR SUNDAY AS THE HIGH SHIFTS OFFSHORE.
THE NAM AND GFS SHOW THE COLD FRONT MOVING INTO THE FORECAST AREA
MONDAY AFTERNOON OR EVENING. THE GFS IS A LITTLE FASTER COMPARED
TO THE NAM. USED AN AVERAGE OF THE MODELS FOR THE TIMING.
CONVERGENCE ASSOCIATED WITH THE FRONT SUPPORTS SHOWERS. COVERAGE
SHOULD BE LIMITED BY THE INITIAL DRYNESS AND LACK OF SIGNIFICANT
UPPER-LEVEL LIFT. PLAN TO CONTINUE THE FORECAST OF CHANCE POPS
WHICH IS SUPPORTED BY THE NAM AND GFS MOS PLUS SREF GUIDANCE. THE
GUIDANCE TEMPERATURES ARE CLOSE.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
EXPECT DRYING BEHIND THE COLD FRONT WILL DOMINATE TUESDAY. THE
GFS AND ECMWF REMAIN CONSISTENT SHOWING DEEP MOISTURE AND
ISENTROPIC LIFT AHEAD OF LOW PRESSURE LIFTING OUT OF THE GULF OF
MEXICO. THE GFS ENSEMBLE GUIDANCE HAS BEEN TRENDING UPWARD WITH
POPS WEDNESDAY. BASED OF THE CONSISTENCY PLAN TO FORECAST
CATEGORICAL POPS WEDNESDAY. EXPECT DRYING BEGINNING THURSDAY
BEHIND THE LOW.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. HIGH CLOUDS
ASSOCIATED WITH AN UPPER LEVEL DISTURBANCE OVER THE CENTRAL GULF
STATES WILL CROSS THE AREA OVERNIGHT. THIS WILL BRING SOME HIGH
CLOUDS TO THE AREA BUT NO PRECIPITATION. WITH DRY AIR DOMINATING
THE LOW LEVELS DO NOT EXPECT ANY FOG. WINDS WILL BE LIGHT AND
VARIABLE THROUGH 14Z...THEN SOUTHWESTERLY AROUND 7 KNOTS FOR THE
REMAINDER OF THE PERIOD.
EXTENDED AVIATION OUTLOOK...MVFR CONDITIONS POSSIBLE LATE MONDAY
AS A COLD FRONT CROSSES THE AREA. MVFR TO IFR CONDITIONS EXPECTED
WEDNESDAY AS A LOW PRESSURE SYSTEM APPROACHES FROM THE GULF COAST.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
