FXUS62 KCAE 290525
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1223 AM EST SUN NOV 29 2009
.SYNOPSIS...
DRY HIGH PRESSURE WILL BE CENTERED NEAR THE FORECAST AREA THROUGH
SUNDAY. AN 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 /06Z SUNDAY THROUGH THURSDAY/...
VFR CONDITIONS THROUGH THE TAF PERIOD. HIGH CLOUDS CONTINUE ACROSS
THE TAF SITES AS A WEAK UPPER LEVEL DISTURBANCE CROSSES THE REGION.
DRY AIR REMAINS IN CONTROL OF THE LOW LEVELS WITH NO FOG EXPECTED
OVERNIGHT. HIGH CLOUDS WILL AGAIN THICKEN TOWARD THE END OF THE TAF
PERIOD AS CLOUDS WELL IN ADVANCE OF A COLD FRONT ENTER THE REGION.
WINDS THROUGH THE PERIOD WILL BE SOUTHWESTERLY AT 7 KNOTS OR LESS.
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.
&&
$$
AVIATION...10
