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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KCHS 242014
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
414 PM EDT FRI MAY 24 2013

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE WILL BUILD INTO THE REGION THIS WEEKEND AND REMAIN
THE DOMINANT WEATHER FEATURE THROUGH LATE NEXT WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --
TONIGHT...THE SHARP UPPER TROUGH OVER THE MID-ATLANTIC WILL
TRANSITION TO A CLOSED LOW AS THE SURFACE HIGH CONTINUES TO BUILD
IN FROM THE NORTHWEST. A MUCH DRIER AND COOLER AIRMASS WILL FILTER
IN THROUGH THE OVERNIGHT...RESULTING IN SIGNIFICANTLY COOLER TEMPS.
IN FACT...LOWS WILL BOTTOM OUT IN THE UPPER 40S IN SOME LOCATIONS
INLAND. THESE MIN TEMPS WILL BE NEARLY 15 DEGREES BELOW CLIMO FOR
LATE MAY...AND WILL APPROACH A RECORD LOW FOR THE DOWNTOWN
CHARLESTON SITE. PLEASE SEE THE CLIMATE SECTION BELOW.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
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A DEEP UPPER TROUGH OVER NEW ENGLAND AND AN UPPER RIDGE OVER THE
CENTRAL PART OF THE COUNTRY WILL PREVAIL THROUGH THE SUNDAY...THEN
WEAK UPPER RIDGING BUILDS OVER THE SOUTHEAST BY MONDAY. AT THE
SURFACE...HIGH PRESSURE WILL BE CENTERED OVER AND NORTH OF THE
REGION ON SATURDAY...THEN SHIFT EAST AND SLIGHTLY SOUTHEAST OF THE
AREA BY SUNDAY AND MONDAY. LIGHT NORTHERLY FLOW BECOMING ONSHORE
NEAR THE COAST FOR SATURDAY WITH HIGHS IN THE UPPER 70S TO AROUND
80...ABOUT 3-5 DEGS BELOW NORMAL. A WEAK FRONT AND MOISTURE
BAND MOVES INTO THE NORTHERN AREA LATER SATURDAY NIGHT AND
SUNDAY...BUT NO PRECIP IS EXPECTED THROUGH SUNDAY. ANOTHER COOL
NIGHT IN THE LOWER TO MID 50S MOST AREAS...CLOSE TO 10 DEGS BELOW
NORMAL FOR SATURDAY NIGHT. HIGH TEMPERATURES BACK CLOSER TO NORMAL BY
SUNDAY IN THE LOWER TO MID 80S...EXCEPT MID TO UPPER 70S NEAR THE
COAST DUE TO AN AFTERNOON SEA BREEZE/ONSHORE FLOW. PARTLY CLOUDY
SUNDAY NIGHT WITH SLIGHTLY WARMER TEMPS...BUT SILL COOLER THAN
NORMAL IN THE MID TO UPPER 50S. BY MONDAY...PARTLY CLOUDY SKIES AS
SOME LOW LEVEL MOISTURE TRIES TO RETURN WITH SSE LOW LEVEL FLOW.
TEMPS BACK IN THE LOWER TO MID 80S. MODELS ARE INDICATING SOME VERY
ISOLATED SHOWERS/TSTMS BY AFTERNOON OVER THE INTERIOR TRI-COUNTY
REGION...BUT HAVE NOT ADDED ANY PRECIP MENTION AT THIS TIME.
-- End Changed Discussion --

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
DECENT MODEL AGREEMENT THIS PERIOD WITH ABOVE AVERAGE FORECAST
CONFIDENCE. UPPER HIGH PRESSURE SHOULD BUILD ACROSS THE REGION
TOWARD THE MIDDLE OF NEXT WEEK LEADING TO WARMING TEMPERATURES AND
SLOWLY INCREASING LOW-LEVEL MOISTURE. RAIN CHANCES WILL REMAIN LOW
GIVEN THE LACK OF DEEP MOISTURE AND FORCING...MAINLY CONFINED TO
INLAND AREAS DURING AFTERNOON PEAK HEATING AS THE SEA BREEZE PUSHES
INLAND.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
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VFR CONDITIONS WILL PREVAIL THROUGH 18Z SATURDAY. GUSTY NW WINDS
WILL DIMINISH THIS EVENING WITH THE LOSS OF HEATING...AND THEN
WINDS WILL VEER AROUND TO MORE NORTHERLY OVERNIGHT.

EXTENDED AVIATION...VFR EXPECTED TO PREVAIL THROUGH EARLY TO MID
NEXT WEEK.
-- End Changed Discussion --

&&

.MARINE...
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TONIGHT...AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST....A
TIGHTENING PRESSURE GRADIENT WILL RESULT IN A SURGE OF N/NE WINDS.
IN FACT...WITH WATER TEMPS IN THE MID 70S AND MUCH COOLER AIR
FILTERING IN GOOD MIXING CONDITIONS WILL BE IN PLACE. MODEL DATA
SUPPORTS A SEVERAL HOUR PERIOD OF LOW-END SMALL CRAFT ADVISORY
CONDITIONS ACROSS ALL WATERS. THE MAIN PARAMETER WILL BE WINDS
GUSTING TO 25 KTS...WITH 6 FT SEAS EXPECTED OUT NEAR 60 NM OVER
THE OUTER GA WATERS. THESE CONDITIONS WILL PERSIST THROUGH THE
OVERNIGHT PERIOD.

NNE WINDS SATURDAY MORNING AT 15 TO 20 KTS WILL DECREASE BY
AFTERNOON AS HIGH PRESSURE SETTLES OVER THE REGION. WINDS EXPECTED
TO BE LIGHT ENOUGH BY AFTERNOON TO BECOME ONSHORE NEAR THE COAST.
LIGHT WINDS OF 10-15 KTS SHOULD BECOME ONSHORE NEAR THE COAST AGAIN
SUNDAY. HIGH PRESSURE WILL REMAIN GENERALLY OVER THE REGION THROUGH
MID WEEK WITH SSE PREVAILING WINDS AND NO HIGHLIGHTS EXPECTED.

RIP CURRENTS...EXPECT A MODERATE RISK TO CONTINUE SATURDAY DUE TO
2-3 FOOT 8-9 SEC SWELLS AND NEW MOON. WOULD NOT BE SURPRISED IF
MODERATE RISK CONDITIONS CONTINUE THROUGH THE WEEKEND.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
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CURRENT INDICATIONS FOR THIS EVENINGS HIGH TIDE INDICATE THAT WE
WILL FALL JUST SHORT OF COASTAL FLOOD ADVISORY CRITERIA AS WINDS
HAVE BEEN OFFSHORE THROUGH MUCH OF THE DAY. THEREFORE WE HAVE
OPTED TO NOT ISSUE AN ADVISORY WITH THIS PACKAGE...THOUGH WE WILL
CONTINUE TO MONITOR TRENDS OVER THE NEXT COUPLE OF HOURS.

HIGH ASTRONOMICAL TIDES DUE TO THE FULL MOON CYCLE AND FAVORABLE
NORTH/NORTHEAST WINDS COULD LEAD TO MINOR SALTWATER INUNDATION
NEAR THE COAST DURING THE HIGH TIDE CYCLES THROUGH THE WEEKEND. BY
THE TIME OF THE HIGH TIDE SUNDAY EVENING AND MONDAY
EVENING...WINDS WILL NOT BE AS CONDUCIVE...YET MINOR SALTWATER
FLOODING WILL STILL BE POSSIBLE AS ASTRONOMICAL FACTORS WILL CAUSE
HIGHER THAN TYPICAL TIDES. COASTAL FLOOD ADVISORIES MAY EVENTUALLY
BE NEEDED.
-- End Changed Discussion --

&&

.CLIMATE...
RECORD LOW TEMPERATURES FOR MAY 25TH...
CHARLESTON INTERNATIONAL AIRPORT /KCHS/.....47 SET IN 1967
DOWNTOWN CHARLESTON /KCHL/..................54 SET IN 1979
SAVANNAH/HHI INTERNATIONAL AIRPORT /KSAV/...49 SET IN 1967

RECORD LOW TEMPERATURES FOR MAY 26TH...
CHARLESTON INTERNATIONAL AIRPORT /KCHS/.....50 SET IN 1979
DOWNTOWN CHARLESTON /KCHL/..................50 SET IN 1979
SAVANNAH/HHI INTERNATIONAL AIRPORT /KSAV/...49 SET IN 1979

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
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GA...NONE.
SC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 8 AM EDT
     SATURDAY FOR AMZ350-352-354-374.
-- End Changed Discussion --

&&

$$

SYNOPSIS...
NEAR TERM...BSH
SHORT TERM...RFM
LONG TERM...RJB
AVIATION...BSH
MARINE...BSH/RFM
TIDES/COASTAL FLOODING...
CLIMATE...