Area Forecast Discussion
Issued by NWS Wilmington, NC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KILM 192220
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
620 PM EDT FRI SEP 19 2014

.SYNOPSIS...
LOW PRESSURE WILL DEVELOP OFF FLORIDA AND MOVE NORTH...PASSING
OFF THE CAROLINA COAST SATURDAY NIGHT AND SUNDAY. THE LOW IS
EXPECTED TO REMAIN FAR ENOUGH OFFSHORE SUCH THAT IMPACTS WILL
REMAIN LIMITED. A COLD FRONT WILL MOVE ACROSS THE AREA MONDAY.
HIGH PRESSURE WILL BUILD DOWN THE COAST ON TUESDAY...BRINGING
COOLER AND DRIER AIR INTO THE REGION ON NORTHEAST WINDS.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 620 PM FRIDAY...EARLY EVENING UPDATE REQUIRED ISOLATED
SHOWER INTRODUCTION OVER OUR FAR INTERIOR ZONES...OTHERWISE
LITTLE TUNING NEEDED AT THIS TIME. THE PREVIOUS AFTERNOON
DISCUSSION FOLLOWS.

AS WE PROGRESS THROUGH TONIGHT AND INTO SAT...MODELS CONTINUE
TO SHOW MODEST MOISTENING OF THE COLUMN THROUGH 25 KFT DUE TO THE
STRONG ONSHORE FLOW. THIS MOISTURE SUPPLY IS DEEPEST ALONG THE
COAST. THIS SCENARIO LENDS ITSELF WELL TO AN INCREASE IN SHOWER
ACTIVITY WITH MORE OFFSHORE CONVECTION MOVING ONSHORE GIVEN THE
PREVAILING FLOW. THE RISK FOR SHOWERS WILL BE HIGHEST ACROSS THE
GRAND STAND AND WINYAH BAY AREA AND PERHAPS ALONG PORTIONS OF THE
SOUTH SANTEE RIVER. THROUGH TONIGHT...WILL CAP POPS AT GOOD CHANCE
IN AND AROUND GEORGETOWN WITH CHANCE POPS ALONG THE REMAINDER OF
THE COAST.

IT WILL BE A BREEZY NIGHT...ESPECIALLY ALONG/NEAR THE COAST. ONSHORE
FLOW SHOULD HELP TO KEEP THE BEACHES NEAR 70 DEG. ELSEWHERE...LOWS
SHOULD DROP TO THE LOWER TO MID 60S...COOLEST ACROSS THE NORTHWEST
CORNER OF THE FORECAST AREA WHERE CLOUD COVER WILL BE THINNEST.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...THE MAIN FEATURE FOR THE WEEKEND CONTINUES TO BE
THE LOW PRESSURE SYSTEM POISED TO DEVELOP JUST OFF THE SOUTHEAST
COAST. MODEL GUIDANCE REMAINS RATHER CONSISTENT AND SEEMS TO BE IN
BETTER AGREEMENT ON PLACEMENT AND STRENGTH FOR LATER SATURDAY INTO
SUNDAY MORNING.

I HAVE INCREASED POPS SLIGHTLY FOR THE COASTAL ZONES AS CONFIDENCE
IS INCREASING THAT MOST AREAS WILL SEE MEASURABLE RAINFALL. THE BEST
LIFT AND MORE IMPORTANTLY MOISTURE ADVECTION OCCURS BETWEEN 1800 UTC
SATURDAY AND 0000 UTC SUNDAY. QPF AMOUNTS WILL BE LESS THAN ONE
QUARTER OF AN INCH WITH MAYBE BALD HEAD ISLAND AND EXTREME EASTERN
BRUNSWICK COUNTY SEEING A BIT MORE. SYSTEM PULLS OFF QUICKLY SUNDAY
LEAVING IN ITS WAKE A RATHER PLEASANT DAY WITH PARTLY SUNNY SKIES.

TEMPERATURE FORECAST HAS REQUIRED LITTLE CHANGE. A COOL DAY
SATURDAY WITH MAX TEMPERATURES ONLY REACHING WITHIN A DEGREE OR TWO
OF 80. INSOLATION BUMPS MAX TEMPERATURES UP ABOUT A CATEGORY SUNDAY.
OVERNIGHT LOWS SHOULD BE A LITTLE WARMER THAN GUIDANCE IS SHOWING
DUE TO OVERCAST SKIES AND MIXED BOUNDARY LAYER.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 3 PM FRIDAY...MONDAY COLD FRONT LOOKING FASTER AND LIKELY
THROUGH BY MORNING. THE AFTERNOON LINGERING PRECIP ALONG THE COAST
DEPICTED BY THE GFS IS ASSOC WITH A HEALTHY VORT MAX COMING THROUGH
THE TROUGH AND IS THUS HARD TO ARGUE WITH. BY TUESDAY HIGH PRESSURE
CENTERED JUST NORTH OF NY WILL SPRAWL ACROSS MOST OF THE EASTERN
U.S. INCLUDING A RIDGE AXIS DOWN INTO THE CAROLINAS. SOME ONSHORE
FLOW OVER FAR SOUTHERN COASTAL ZONES MAY SPONSOR SOME CLOUDINESS AND
PERHAPS A STRAY SPRINKLE. THE CENTER OF THE HIGH DROPS SLOWLY SOUTH
AND EAST WEDNESDAY INTO THURSDAY WHILE THE RIDGE AXIS HOLDS TOUGH.
THERE MAY BE A SLIGHT NORTHWARD CREEP OF THE ONSHORE FLOW AND DEEPER
MOISTURE. TEMPERATURES WILL AVERAGE A JUST A FEW DEGREES SHY OF
CLIMATOLOGY FOR JUST ABOUT EVERY DAY OF THE LONG TERM.

&&

.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
AS OF 18Z...STRONG WEDGE WILL CONTINUE THROUGH THE FORECAST PERIOD.
GRADIENT WILL BE QUITE STRONG...WITH EAST NORTHEAST WINDS ALONG THE
COAST GUSTING TO AROUND 25 KTS. THERE WILL BE SHOWERS ALONG THE
PERIPHERY OF THE WEDGE...AND THERE IS A POSSIBILITY OF CONVECTION
ALONG THE EXTREME WESTERN PORTION OF THE CWA...AS WELL AS THE COAST.
COVERAGE WILL BE QUITE LIMITED HOWEVER. WINDS WILL REMAIN GUSTY
TONIGHT...BUT NOT QUITE AS STRONG. A NOCTURNAL ONSHORE SHOWER IS
POSSIBLE AT THE MYRTLES NEAR SUNRISE...CONTINUING THROUGH THE END OF
THE FORECAST PERIOD WITH INTERMITTENT MVFR CONDITIONS EXPECTED. AS
THE LOW AND MOISTURE MOVE NORTHWARD...ILM WILL SEE SOME SCATTERED
CONVECTION TOWARD MIDDAY SATURDAY.

EXTENDED OUTLOOK...CHANCE OF SHOWERS ALONG THE COAST SAT EVENING.
GUSTY NORTHEAST WINDS SAT WILL BECOME NORTHWEST ON SUN AS LOW
PRESSURE WELL OFFSHORE MOVES UP THE EAST COAST. SLIGHT CHANCE OF A
SHOWER WITH A COLD FRONT MONDAY. VFR TUE AND WED.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 620 PM FRIDAY...SMALL CRAFT ADVISORY REMAINS IN EFFECT.
STRONG HIGH PRESSURE CENTERED ACROSS NEW ENGLAND WILL WEDGE
STRONGLY ACROSS THE EASTERN CAROLINAS INTO SATURDAY. MEANTIME...A
PRONOUNCED INVERTED TROUGH POKING UP THE SOUTHEAST COAST FROM
OFFSHORE OF FLORIDA WILL SHARPEN AS IT EXPANDS NORTH. LOW PRESSURE
MAY DEVELOP IN THIS AREA TOWARD SAT MORNING. THIS WILL KEEP A
RATHER TIGHT PRESSURE GRADIENT IN PLACE. SUSTAINED EAST-NORTHEAST
WINDS WILL BE UP TO 20 TO 25 KT AND GUSTY. SEAS WILL BE UP TO 6 TO
7 FT.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 3 PM FRIDAY...HEALTHY NORTHEAST WINDS ON THE ORDER OF 15-20
KNOTS WILL CONTINUE SATURDAY INTO SATURDAY NIGHT AS LOW PRESSURE
DEVELOPS OFF THE SOUTHEAST COAST AND MOVES WELL OFFSHORE. I HAVE
EXTENDED THE SMALL CRAFT ADVISORY FOR ALL WATERS SATURDAY AND THE
NORTH CAROLINA WATERS INTO EARLY SUNDAY MORNING. SEAS WILL ECLIPSE
THE SIX FOOT CRITERIA MAINLY ON THE OUTER FRINGES OF THE ZONES. A
MORE MODEST NORTHWEST FLOW...10-15 KNOTS WILL DEVELOP EARLY SUNDAY
AND PERSIST MOST OF THE DAY. SIGNIFICANT SEAS WILL DIMINISH SUNDAY
AS WELL INTO A RANGE OF 2-3 FEET.

LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 3 PM FRIDAY...EARLY MONDAY COLD FRONTAL PASSAGE VEERS WINDS TO
A NORTHERLY DIRECTION. THE GRADIENT WILL INITIALLY BE RATHER WEAK
AND SEAS GENERALLY 2 TO 3 FT. AS THE GRADIENT PINCHES TUESDAY AND
WEDNESDAY WINDS WILL RAMP UP INTO THE 15 TO 20 KT REALM. A FEW
ADVISORY-WORTHY SEAS APPEAR POSSIBLE BY WEDNESDAY ACROSS ALL BUT
HORRY CTY WHERE WAVE SHADOWING WILL LIKELY PRECLUDE ADVISORY. SCEC
MAY BE NEEDED HOWEVER.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...

SC...NONE.
NC...COASTAL FLOOD ADVISORY UNTIL 9 PM EDT THIS EVENING FOR NCZ107.

MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT SATURDAY FOR AMZ254-256.
         SMALL CRAFT ADVISORY UNTIL 2 AM EDT SUNDAY FOR AMZ250-252.

&&

$$

NEAR TERM...RJD/MJC
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...MRR
MARINE...RJD/SHK/MBB





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.