FXUS62 KCHS 170659 AAA
AFDCHS

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE CHARLESTON SC
255 AM EDT FRI SEP 17 2004

.SHORT TERM /TODAY AND TONIGHT/...

UPDATED...WILL GO WITH A LAKE WIND ADVISORY FOR LAKE MOULTRIE WITH 
WINDS OF AT LEAST 15 TO 25 KT EXPECTED. A QUICK CHECK OF THE 
PINEVILLE OB INDICATES WINDS CURRENTLY AROUND 20 MPH WITH GUSTS NEAR 
25 MPH.

A COUPLE OF BROKEN LINES OF SHOWERS WITH ISOLATED TSTMS ARE MOVING 
THROUGH THE AREA. DAMAGING WIND GUSTS ARE STILL POSSIBLE WITH THIS 
ACTIVITY PARTICULARLY IF ANY STORMS CAN GET PARTICULARLY ORGANIZED. 
WINDS HAVE BECOME UNIDIRECTIONAL BASED ON THE VWP BUT SOME LOW LVL 
SE FLOW IN THE VERY LOWEST LAYERS SEEN ON FIRST GLIMPSE OF 06Z 
SOUNDING. TORNADO THREAT LOOKS TO BE MINIMAL AT THIS TIME. WITH THE 
EXPECTED RAPID MOVEMENT OF ANY SHOWERS AND TSTMS THAT DEVELOP DO NOT 
ANTICIPATE A BIG FLOODING THREAT. IF ECHOES TRAIN REPEATEDLY ACROSS 
THE SAME AREA...COULD SEE PROLONGED HEAVY RAIN AND A QUICK INCH OR 
SO IS POSSIBLE BUT A WIDESPREAD FLOODING EVENT IS CERTAINLY NOT 
EXPECTED. HEAVIER DOWNPOURS ARE EXPECTED LATER THIS MORNING INTO 
THIS AFTN AFTER ANY POTENTIAL HEATING ACTS TO DESTABILIZE THE 
ATMOSPHERE.

DRYER MID LVL AIR TO MOVE INTO THE WRN FRINGE OF THE AREA LATER 
TODAY THEN INTO THE EASTERN PORTIONS TONIGHT. BEST CHANCE OF PRECIP 
ACTUALLY LOOKS TO BE THE NRN SECTIONS FOR TODAY CLOSER TO DECENT 
DYNAMICS THAT SHOULD SWING THROUGH AND ALSO COINCIDE WITH DEEPER 
MOISTURE. PLAN TO GO WITH AT LEAST 70 POPS FOR THE NRN SECTIONS AND 
TAPER OFF TO 50 OR SO ON THE GA COAST.

BIG PROBLEM TODAY COULD BE GUSTY WINDS WITH UP TO 45 KT AT 3KFT. 
WILL TAKE UNTIL LATER IN THE DAY FOR UPR LVL WINDS TO REALLY DROP 
MUCH. EXPECT BREEZY CONDITIONS FOR TODAY PARTICULARLY IF THE SUN CAN 
POKE OUT AT TIMES.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...A VERY INTERESTING PATTERN 
SETTING UP FOR THE FORECAST PERIOD. SHORT TERM MODELS ARE CONVERGING 
ON A SOLN MORE SO THAN PREV RUNS. THE UPR LVL REMNANTS OF IVAN ARE 
FCST TO MOVE NE THEN DROP BACK TO THE S OVER SC AND GA AS IT GETS 
CAUGHT UP IN A FRONTL BNDRY. THE SFC REFLECTION SHOULD COINCIDE 
UNTIL IT GETS LOST FCST FRNTL BNDRY ALONG THE COAST ON SAT NIGHT AND 
SUN. THE BEST CHANCE OF RAIN ACTUALLY LOOKS TO BE SAT NIGHT INTO SUN 
NIGHT WITH UPR LOW MOVING THROUGH AND A RETURN OF DEEPER MOISTURE. 
ONSHORE FLOW TO REMAIN IN PLACE BEHIND THE FRONT FOR NEXT WEEK WITH 
MAINLY LOW LVL MOISTURE BUT SOME LIFT AND POSSIBLE COASTAL TROF AS 
HIGH PRES BUILDS DOWN THE COAST. NET RESULT WILL BE A LINGERING 
CHANCE OF PRECIP THROUGH THE WEEK. TPC FCST HAS BEEN BRINGING JEANNE 
INTO THE SC AND OR GA COAST SOME TIME ON TUE FOR THE PAST COUPLE OF 
FCST RUNS. WOULD NOT BE SURPRISED TO SEE A SLOWER SOLN ON THE NEXT 
PACKAGE GIVEN THE WIDE  VARIETY OF MODEL SOLUTIONS AVAILABLE. DO NOT 
PLAN TO MAKE MANY CHANGES FOR THE END OF THE FORECAST PERIOD.

&&

.MARINE...
WINDS HAVE SWUNG AROUND TO SLY ALL WATERS EARLY THIS MORNING WITH A
SOLID 20 TO 25 KT REPORTED BOTH NEAR AND OFFSHORE. SEAS HAVE BUILT 
TO 7 TO 9 FT OFF THE GEORGIA COAST AND WERE LIKELY BUILDING TO 5 TO 
7 FT ALONG THE SOUTH CAROLINA COAST. WILL INITIALIZE WITH SCA ALL 
WATERS THIS MORNING WITH FLOW SLOWLY BECOMING MORE SW WITH TIME THRU 
TONIGHT. THE LATEST GUIDANCE IS FASTER BUILDING HIGH PRES DOWN THE 
MID ATLC COAST AND HAVE MADE CHANGES SAT AND SUN VEERING WINDS TO W 
AND NW...THEN NE BY EARLY SUNDAY. THE SFC PRES GRADIENT SHOULD 
BECOME TIGHTER MON AND TUE...LARGELY DEPENDANT ON WHERE TS OR HRCN 
JEANNE IS LOCATED. SEA HEIGHTS IN THE LATTER PERIODS PROBLEMATIC...
PLAN TO MAKE SOME LAST MINUTE ADJUSTMENTS WITH COORD FROM SURROUNDING
OFFICES.

&&

.AVIATION...
GUSTY S WINDS CURRENTLY AT BOTH TERMS WITH A BKN LINE OF CONVECTION
POSSIBLY SET TO BRUSH SAVANNAH IN THE 09Z-13Z TIME FRAME AND A BIT 
LATER AT CHS. THE CHS TERM IS TRICKIER AS CONVECTION FIRING OVER THE 
OCEAN IS POISED TO MOVE ONSHORE AT ANY TIME THIS MORNING. SCT-BKN 
CIGS 015-025 THRU 15Z WITH MVFR CIGS POSSIBLY LINGERING A BIT 
LONGER. KEPT WIND GUSTS ALL DAY WITH HIGHER CONFIDENCE AT CHS AFTER 
15Z. ENDED RAIN AT SAV TERM AROUND 12Z BUT KEPT SOME PROBS TDA 
FURTHER UPSTREAM AT CHS.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY FOR LAKE MOULTRIE.
MARINE...SMALL CRAFT ADVISORY AMZ330-350-352-354-374.

&&

$$

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