Area Forecast Discussion
Issued by NWS Charleston, SC

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000
FXUS62 KCHS 261501
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1001 AM EST WED NOV 26 2014

.SYNOPSIS...
A STRENGTHENING AREA OF LOW PRESSURE OFF THE CAROLINA COAST EARLY
THIS MORNING WILL TRACK NORTHEAST ALONG A STALLED FRONT...LIFTING
AWAY FROM THE REGION BY THIS AFTERNOON. HIGH PRESSURE WILL THEN
BUILD INTO THE SOUTHEAST UNITED STATES AND PREVAIL THROUGH EARLY
NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AN AMPLIFIED MID LATITUDE AND DEEP LAYERED TROUGH IS CENTERED OVER
THE EASTERN US INTO THE GULF THIS MORNING...WITH A ROBUST SHORT
WAVE TROUGH EMBEDDED WITHIN THAT WILL SWEEP THROUGH THE ENTIRE
FORECAST AREA BY EARLY AFTERNOON. THIS PROMINENT DISTURBANCE
DRIVEN BY A POWERFUL 175 KT OR GREATER UPPER JET IS RESPONSIBLE
FOR THE DEEPENING AREA OF LOW PRESSURE THAT IS FOUND HUGGING THE
MID ATLANTIC COAST AND WILL INTENSIFY FURTHER AS IT HEADS RAPIDLY
TO THE SOUTH OF LONG ISLAND BY NIGHTFALL.

NOW THAT THE PERSISTENT FETCH OF DEEP TROPICAL MOISTURE HAS
FINALLY CLEARED INTO THE ATLANTIC...ONCE THE SHORT WAVE ALOFT
MOVES THROUGH AROUND 11 AM-2 PM FROM WEST/SW TO EAST/NE WE/LL
EXPERIENCE AN END TO OUR LINGERING RAINS AND DRIZZLE. THIS WILL BE
FOLLOWED BY A FAIRLY RAPID CLEARING IN A SIMILAR FASHION FROM
WEST/SW TO EAST/NE. THIS CLEARING IS DEFINED BY A SHARP
DEMARCATION THAT FOLLOWS QUICKLY ON THE HEELS OF THE SHORT
WAVE...AND IS CLEARLY EVIDENT ON SATELLITE IMAGERY. THE BACK EDGE
OF THE CLOUDS ARE MOVING EAST AT ALMOST 40 MPH...WHICH IF IT
MAINTAINS THAT VELOCITY WOULD PUT THE CLEARING LINE THROUGH PLACES
SUCH SPRINGFIELD AND HINESVILLE BY 11-12 PM...SAVANNAH AND
RIDGEVILLE BY 12-1 PM...BEAUFORT AND SUMMERVILLE BY 1-2 PM AND
FINALLY THROUGH CHARLESTON BY 2-3 PM.

WHAT INSOLATION WE DO GET TODAY WILL SPEND A GOOD DEAL OF ENERGY
EVAPORATING ALL THE RECENT RAINS WE HAVE RECEIVED. AND THAT
ALONG WITH CONTINUED COOL ADVECTION...ALBEIT WEAK...WILL LIMIT
HIGHS THIS AFTERNOON TO THE MID 50S NORTH AND UPPER 50S TO MAYBE
NEAR 60 SOUTH.

LAKE WINDS...BASED ON RECENT OBSERVATIONS AND CONTINUED DECENT
ISALLOBARIC PRESSURE RISES ACROSS LAKE MOULTRIE...WE HAVE
EXTENDED THE LAKE WIND ADVISORY INTO EARLY AFTERNOON.

TONIGHT...THE AXIS OF THE UPPER LEVEL TROUGH WILL MOVE THROUGH...ALONG
WITH A REINFORCING COLD FRONT AT THE SURFACE. THE FRONTAL PASSAGE
AND WILL BE DRY GIVEN LIMITED MOISTURE...BUT SOME MID LEVEL CLOUDS
COULD ACCOMPANY THE FRONT WITH A SIGNIFICANT UPPER DISTURBANCE
PASSING INTO THE CAROLINAS. WINDS COULD BECOME LIGHT IN THE
EVENING...BUT MAY RECOUPLE AS COLD AIR ADVECTION DEVELOPS IN WAKE
OF THE FRONT LATE. EXPECT LOWS IN THE UPPER 30S TO AROUND 40.


&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
THURSDAY THROUGH SATURDAY...THE AXIS OF AN UPPER LEVEL TROUGH WILL
LIFT ACROSS THE NORTHEAST COASTLINE ON THURSDAY...FOLLOWED BY A
LESS AMPLIFIED PATTERN ALOFT FRIDAY AND SATURDAY. STRONG SURFACE
HIGH PRESSURE WILL BUILD INTO THE REGION FROM THE NORTHWEST
THURSDAY AND EVENTUALLY BECOME SITUATED ALONG THE EAST COAST
THROUGH SATURDAY. DRIER AIR AND THE LACK OF ANY NOTABLE SYNOPTIC
FORCING WILL SUPPORT RAIN FREE WEATHER LATE WEEK INTO THE
WEEKEND...AND WILL CONTINUE TO ADVERTISE RAIN CHANCES AT ZERO.
COLD ADVECTION ON THE PERIPHERY OF THE BUILDING SURFACE HIGH WILL
SUPPORT UNSEASONABLY COOL CONDITIONS FOR THURSDAY AND
FRIDAY...WITH HIGH TEMPERATURES SUPPRESSED IN THE 50S BOTH
AFTERNOONS. LOW TEMPERATURES THURSDAY AND FRIDAY NIGHTS WILL ALSO
REFLECT THE COLD AIR MASS IN PLACE. COLD ADVECTION THURSDAY NIGHT
WILL ALLOW TEMPERATURES TO FALL INTO THE LOW TO MID 30S...WHILE
IMPROVED RADIATIONAL COOLING CONDITIONS UNDER CLEAR SKIES AND
LIGHT WINDS FRIDAY NIGHT WILL SUPPORT TEMPERATURES RIGHT AROUND
FREEZING FOR INLAND AREAS. EXPECT A WARMING TREND TO BEGIN ON
SATURDAY...AS THE SURFACE HIGH PUSHES TOWARD THE COASTLINE AND A
RIDGE BUILDS ALOFT. HIGHS ON SATURDAY WILL REACH THE UPPER 50S FAR
NORTH TO THE LOW/MID 60S FARTHER SOUTH...STILL SEVERAL DEGREES
BELOW NORMAL.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
THE CENTER OF SURFACE HIGH PRESSURE WILL SLOWLY SETTLE OVER THE
NEARBY ATLANTIC WATERS LATE SATURDAY INTO MONDAY...WHILE AN UPPER
RIDGE BUILDS FROM THE EASTERN GULF OF MEXICO. EXPECT A WARMING
TREND TO CONTINUE THROUGH MONDAY AS A RESULT...WITH HIGH
TEMPERATURES REBOUNDING INTO THE UPPER 60S TO AROUND 70 DEGREES
SUNDAY AND MONDAY AFTERNOON...AND NIGHTTIME LOWS FALLING INTO THE
40 DEGREE RANGE. A COLD FRONT FORMING THE LEADING EDGE OF ANOTHER
STRONG SURFACE HIGH PRESSURE WILL APPROACH FROM THE NORTHWEST ON
TUESDAY. THE FRONT COULD STALL OVER OR JUST NORTH OF THE FORECAST
AREA WEDNESDAY...AS THE SURFACE HIGH BUILDS AN INLAND WEDGE FROM
THE MID ATLANTIC STATES INTO THE CAROLINAS AND NORTHERN GEORGIA.
NORTHEAST FLOW WITHIN THIS PATTERN WILL CONTRIBUTE TO A SLIGHT
COOL DOWN FOR THE MID WEEK PERIOD. A COASTAL TROUGH ON THE EDGE OF
THE INLAND WEDGE COULD SUPPORT A SLIGHT CHANCE FOR RAIN LATE
TUESDAY INTO WEDNESDAY.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
FLIGHT RESTRICTIONS WILL CONTINUE AT THE TERMINALS THROUGH 17-18Z
AT KSAV AND UNTIL 19-20Z AT KCHS BEFORE VFR WEATHER FINALLY
RETURNS. WINDS WILL BE GUSTY TODAY AS THE COASTAL STORM DEPARTS
AND COOLER AND DRIER AIR WORKS IN FROM THE WNW.

EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL.

&&

.MARINE...
THE INTENSIFYING LOW PRESSURE SYSTEM WILL RAPIDLY PULL AWAY TO
THE NORTHEAST AND MAINTAIN HAZARDOUS MARINE CONDITIONS THIS
MORNING SOUTH AND INTO THIS AFTERNOON NORTH...DUE TO THE ASSOCIATED
TIGHT PRESSURE GRADIENT AND COLD ADVECTION MIXING OVER THE WATERS
FROM A STRONG LOW LEVEL WIND FIELD. GALE CONDITIONS OVER THE
GEORGIA AND FAR SOUTHERN SOUTH CAROLINA WATERS THIS MORNING...WITH
SOLID SMALL CRAFT ADVISORY CONDITIONS ALONG THE CHARLESTON COUNTY
COAST AND IN CHARLESTON HARBOR. CONDITIONS SHOULD BRIEFLY IMPROVE
THIS AFTERNOON AND EVENING AS THE LOW PULLS AWAY AND THE GRADIENT
RELAXES...BUT ANOTHER SURGE OF COLD AIR ADVECTION IS EXPECTED
LATER TONIGHT AS A STRONG UPPER DISTURBANCE MOVES THROUGH. SMALL
CRAFT ADVISORIES COULD THEREFORE BE NEEDED AGAIN FOR PORTIONS OF
THE MARINE ZONES IN THE LATE TONIGHT TIME FRAME.

THURSDAY THROUGH SUNDAY...ANOTHER SURGE OF COLD AIR ADVECTION IS
EXPECTED THURSDAY...ALONG WITH A TIGHTENING PRESSURE GRADIENT ON
THE EDGE OF HIGH PRESSURE BUILDING INLAND. SMALL CRAFT ADVISORIES
COULD THEREFORE BE NEEDED AGAIN FOR PORTIONS OF THE MARINE ZONES
THROUGH THURSDAY. MARINE CONDITIONS WILL THEN IMPROVE FOR FRIDAY
INTO THE WEEKEND...AS THE SURFACE HIGH SHIFTS TOWARD THE WATERS
AND THE GRADIENT RELAXES.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR SCZ045.
MARINE...GALE WARNING UNTIL 11 AM EST THIS MORNING FOR AMZ352-354.
     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR AMZ350.
     GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR AMZ374.
     SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR AMZ330.

&&

$$

NEAR TERM...
SHORT TERM...WMS
LONG TERM...WMS
AVIATION...
MARINE...WMS





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