FXUS62 KCAE 260255
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
955 PM EST WED NOV 25 2009
.SYNOPSIS...
LOW PRESSURE OFF THE GEORGIA AND SOUTH CAROLINA COAST TONIGHT WILL
MOVE WELL NORTHEAST OF THE FORECAST AREA THURSDAY. COLD HIGH
PRESSURE WILL BECOME DOMINATE AS THE LOW LIFTS NORTHEASTWARD. THE
COLDEST AIR OF THE SEASON SO FAR WILL BE ASSOCIATED WITH THIS AIR
MASS.
&&
.NEAR TERM /UNTIL 8 AM THURSDAY MORNING/...
SOME FOG STARTING TO DEVELOP OVER THE REGION. SHORT TERM MODELS
KEEP VSBYS PRETTY MUCH UP TO 4-5 MILES BUT WITH SKIES CLEARING OFF
AND NEARLY CALM WINDS AND TEMPERATURES DROPPING CLOSE TO DEWPOINTS
...THERE COULD BE SOME LOWER VSBYS. SO HAVE DECIDED TO MENTION
PATCHY DENSE FOG IN GRIDS 09Z-13Z AND WILL ISSUE UPDATED ZONE
PACKAGE. OTHERWISE...LOW TEMPERATURES STILL THE SAME.
PREVIOUS DISCUSSION...
THE WATER VAPOR IMAGERY SHOWS A PROGRESSIVE PATTERN. MID-LEVEL
DRYING SHOULD OVERSPREAD THE REGION EARLY. THE MODELS ARE
CONSISTENT KEEPING DEEP MOISTURE ASSOCIATED WITH THE OFFSHORE LOW
EAST OF THE FORECAST AREA. THE RAIN CHANCE APPEARS VERY LOW. THE
TEMPERATURE GUIDANCE IS CLOSE.
&&
.SHORT TERM /8 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
DRY HIGH PRESSURE WILL DOMINATE. WIND SHOULD HELP HOLD UP
TEMPERATURES THURSDAY NIGHT...BUT IT SHOULD BE COLDER FRIDAY NIGHT
AS THE PRESSURE GRADIENT RELAXES. THE TEMPERATURE GUIDANCE IS CLOSE
WITH LOWS IN THE MID TO UPPER 30S THURSDAY NIGHT AND AROUND FREEZING
FRIDAY NIGHT. WE HAVE NOTED THE COLD TEMPERATURES IN THE HAZARDOUS
WEATHER OUTLOOK.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
THE DRY RIDGE SHOULD CONTINUE TO DOMINATE SATURDAY AND SUNDAY.
LOWS WILL PROBABLY BE AROUND FREEZING SATURDAY NIGHT WITH STRONG
RADIATIONAL COOLING. THE GFS AND ECMWF SHOW AN INCREASE IN
MOISTURE MONDAY ASSOCIATED WITH AN APPROACHING COLD FRONT. THE
MODELS SHOW THE FRONT STALLING WITH A POSSIBLE WAVE DEVELOPING
ALONG THE FRONT. THE GFS ENSEMBLE MEANS SUPPORT CHANCE POPS MONDAY
THROUGH WEDNESDAY.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
WEAK COLD FRONT TO OUR WEST WITH A WEAK AREA OF LOW PRESSURE OFF THE
CAROLINA COAST. SKIES SLOWLY BEGINNING TO CLEAR FROM THE WEST.
MAINLY SCTD-BKN CIRRUS THROUGH 06Z THURSDAY...BECOMING MOSTLY CLEAR
THEREAFTER. MAIN CONCERN WILL BE HOW MUCH FOG MAY DEVELOP DURING THE
OVERNIGHT HOURS WITH PLENTIFUL LOW-LEVEL MOISTURE AND LIMITED
MIXING. WILL MENTION MVFR FOG 08Z-12Z WITH BRIEF IFR FOG DURING THAT
TIME PERIOD. HIGH PRESSURE WILL BUILD IN FROM THE WEST THURSDAY SO
SKIES SHOULD BE MOSTLY CLEAR AFTER 13Z UNTIL THE END OF THE TAF
PERIOD.
EXTENDED AVIATION OUTLOOK...MAINLY VFR CONDITIONS EXPECTED THROUGH
THE PERIOD.
.HYDROLOGY...
RESERVOIR RELEASES HAVE PROMPTED A FLOOD WARNING FOR MODERATE
FLOODING OF SWAMPLANDS DOWNSTREAM FROM THE SANTEE DAM IN CLARENDON
COUNTY. THIS FLOODING SHOULD CONTINUE FOR SEVERAL DAYS.
&&
.HYDROLOGY...
RESERVOIR RELEASES HAVE PROMPTED A FLOOD WARNING FOR MODERATE
FLOODING OF SWAMPLANDS DOWNSTREAM FROM THE SANTEE DAM IN CLARENDON
COUNTY. THIS FLOODING SHOULD CONTINUE FOR SEVERAL DAYS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...07
SHORT TERM...
LONG TERM...
AVIATION...22
HYDROLOGY...
