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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KCHS 171417
AFDCHS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1017 AM EDT FRI MAY 17 2013

.SYNOPSIS...
AN UPPER DISTURBANCE WILL MOVE NORTH OF THE AREA THROUGH THE WEEKEND
AS ATLANTIC HIGH PRESSURE BUILDS ACROSS THE REGION. HIGH PRESSURE
WILL BE THE DOMINANT FEATURE THROUGH MUCH OF NEXT WEEK BEFORE A COLD
FRONT POSSIBLY APPROACHES ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
ATLANTIC HIGH PRESSURE WILL ONCE AGAIN REMAIN THE DOMINANT WEATHER
FEATURE TODAY. MAIN FORECAST ISSUE WILL REVOLVE AROUND POTENTIAL
PRECIP THIS AFTERNOON. MODELS ARE A BIT SCATTERED ON SHOWING
DEVELOPMENT...WITH MOST NOT SHOWING MUCH OVER OUR FORECAST AREA. HAVE
MAINTAINED LOW END SLIGHT CHANCES WEST OF I-95 AS COVERAGE...IF
ANY...WILL BE VERY ISOLATED. OVERALL...PARAMETERS ARE NOT THAT
FAVORABLE FOR DEEP MOIST CONVECTION...AS SHEAR IS WEAK AND
FORECAST SOUNDINGS ARE PRETTY DRY.

OTHERWISE...EXPECT ANOTHER PLEASANT DAY. SHOULD SEE MORE SUNSHINE
AND WARMER TEMPERATURES THAN THURSDAY...WITH HIGHS IN THE MID AND
UPPER 80S. NO MAJOR CHANGES WERE NEEDED WITH THIS UPDATE.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
DRY WEATHER ANTICIPATED TONIGHT WITH A SHORT WAVE RIDGE BUILDING
ACROSS GEORGIA AND THE CAROLINAS. OCCASIONAL MID/HIGH CLOUDS WILL
PASS THROUGH THE REGION WITH LOWS IN THE 60S...SIMILAR TO READINGS
ON FRI MORNING.

AN UPPER SHORTWAVE WILL DRIFT SOUTHEAST FROM THE OHIO VALLEY INTO
NORTH CAROLINA SATURDAY THROUGH MONDAY. ALTHOUGH THE BRUNT OF THE
VORTICITY WILL STAY NORTH OF THE FORECAST AREA...THE UPPER HEIGHT
FALLS WILL PRODUCE A MORE FAVORABLE ENVIRONMENT FOR SHOWERS AND
THUNDERSTORMS. LOW-LEVEL MOISTURE WILL INCREASE SUBSTANTIALLY SUNDAY
INTO MONDAY WHEN THE UPPER VORT MAKES ITS CLOSEST APPROACH. ON
SATURDAY THE SEABREEZE SHOULD BE THE PRIMARY DRIVER FOR CONVECTION.
SUNDAY INTO MONDAY THE COVERAGE SHOULD BE A BIT GREATER AS
MID-LEVELS COOL SLIGHTLY IN CONCERT WITH INCREASING LOW-LEVEL
MOISTURE. WE HAVE 30-40 POPS BOTH DAYS...WITH SLIGHT CHANCES DURING
THE OVERNIGHT HOURS. HIGH TEMPS WILL BE SOLIDLY IN THE 80S WITH LOWS
IN THE 60S.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
THE UPPER SHORTWAVE NORTH OF THE AREA ON MONDAY WILL ESSENTIALLY
DISSOLVE ACROSS THE EASTERN CAROLINAS ON TUESDAY LEAVING A VERY WEAK
RIDGE PATTERN IN PLACE. ATLANTIC HIGH PRESSURE WILL PRODUCE AN
ONSHORE FLOW WITH SEA BREEZES DEVELOPING EACH AFTERNOON. SURFACE
DEWPOINTS WILL PERSIST IN THE MIDDLE 60S WITH HIGHS CLIMBING WELL
INTO THE 80S EACH DAY. ALTHOUGH THERE ARE NO STRONG FORCING
MECHANISMS...WE KEPT ISOLATED SHOWERS AND THUNDERSTORMS IN THE
FORECAST EACH AFTERNOON/EVENING. A COLD FRONT COULD MOVE INTO THE
AREA ON FRIDAY.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
VFR CONDITIONS WILL PREVAIL AT KCHS AND KSAV THROUGH 12Z SATURDAY.

EXTENDED AVIATION OUTLOOK...PRIMARILY VFR. ISOLATED TO SCATTERED
AFTERNOON SHOWERS/THUNDERSTORMS EXPECTED EACH AFTERNOON THROUGH
EARLY NEXT WEEK.

&&

.MARINE...
THROUGH TONIGHT...THE LOW LEVEL RIDGE AXIS REMAINS CONSTANT AND
SO DOES OUR FORECAST WITH A SOUTHERLY COMPONENT LESS THAN 15 KT
AND SEAS 3 FT OR LESS. DIRECTIONS SHOULD BACK A BIT MORE SE ALONG
THE GEORGIA COAST THIS AFTERNOON AS THE LAND WARMS AND THE SEA
BREEZE PUSHES INLAND.

ATLANTIC HIGH PRESSURE WILL BE THE PRIMARY MARINE INFLUENCE THROUGH
THE PERIOD WITH SOUTHERLY FLOW PREVAILING. WIND SPEEDS WILL PERSIST
IN THE 10-15 KT RANGE WITH SEAS 4 FT OR LESS.

&&

.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...
NEAR TERM...ECT
SHORT TERM...JRL
LONG TERM...JRL
AVIATION...ECT
MARINE...ECT/JRL