Area Forecast Discussion
Issued by NWS Wilmington, NC

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000
FXUS62 KILM 230244
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
943 PM EST SAT NOV 22 2014

.SYNOPSIS...
CLOUDS WILL INCREASE OVERNIGHT AHEAD OF A STORM SYSTEM TAKING
SHAPE IN THE GULF OF MEXICO. THIS SYSTEM WILL BRING MILD AND WET
WEATHER SUNDAY AND MONDAY AS IT LIFTS NORTHEAST. STRONG
THUNDERSTORMS WILL BE POSSIBLE LATE SUNDAY THROUGH EARLY MONDAY. A
COLD FRONT WILL CROSS THE COAST EARLY TUESDAY...STALLING OFFSHORE.
DEEPENING LOW PRESSURE WILL FORM ALONG THIS FRONT...BRINGING A COOL
WET CONDITIONS WEDNESDAY. CLEARING WEATHER IS EXPECTED THANKSGIVING
DAY WITH BELOW NORMAL TEMPERATURES THROUGH NEXT WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 640 PM SATURDAY...HIGH CLOUDS ARE OVERSPREADING THE CAROLINAS
WHILE MOISTURE ALSO INCREASES IN THE LOW LEVELS DUE TO
EAST-SOUTHEASTERLY FLOW OFF THE ATLANTIC OCEAN. IT SHOULD ONLY TAKE
ANOTHER 3-5 HOURS TO SEE MOSTLY CLOUDY TO CLOUDY SKIES IN PLACE
ACROSS THE ENTIRE FORECAST AREA...AND MORE IMPORTANTLY TO SEE RAIN
DEVELOPING ACROSS NE SOUTH CAROLINA. BASED ON THE LATEST RADAR
SUMMARY AND 23Z HRRR RUNS...I HAVE SPED UP THE INTRODUCTION OF RAIN
CHANCES TO THE FORECAST BY SEVERAL HOURS AND HAVE INCREASED POPS
THROUGH DAYBREAK AS WELL. EVEN ACROSS THE SANTEE RIVER RIVER AREA I
STILL ONLY THINK A FEW HUNDREDTHS OF AN INCH WILL FALL BEFORE
DAYBREAK. MORE SUBSTANTIAL MOISTURE ADVECTION AND SYNOPTIC FORCING
WILL ARRIVE DURING THE DAY TOMORROW.

TEMPERATURES SHOULD BE VERY NEAR THEIR LOWEST READINGS OF THE NIGHT
NOW. RADIATIONAL COOLING CONDITIONS SHOULD DETERIORATE FROM THIS
POINT FORWARD AS CLOUD COVERAGE INCREASES. AFTER DRAWING THE LATEST
HOURLY TEMPERATURE CURVES IN THE DIGITAL FORECAST I NOTED THE TEXT
FORMATTER USED THE "RISING TEMPERATURE" PHRASE FOR SOME COASTAL
ZONES TONIGHT. THIS IS GOOD AND DESCRIBES THE ANTICIPATED SHAPE OF
HOURLY TEMPERATURE CURVES NEAR THE COAST.

&&

.SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/...
AS OF 336 PM SATURDAY...PRIMARY HEADLINE THIS PERIOD...STRONG TO
SEVERE TSTM POTENTIAL LATE SUNDAY THROUGH EARLY MONDAY. LOW-LEVEL
SE WINDS WILL INTENSIFY...TRANSPORTING MOISTURE RICH GULF STREAM
AIR INTO THE COASTAL ZONES ELEVATING BOUNDARY LAYER DEWPOINTS.
A DEVELOPING AXIS OF POSITIVE MIXED-LAYERED CAPES WILL ORIENT
ITSELF ALONG OR JUST OFF THE COAST SUNDAY NIGHT THROUGH MONDAY
MORNING. THE HIGHEST HELICITY VALUES FAR PRECEDE THE MAXIMUM OF
ML-CAPE BUT SOME OVERLAP OF MODERATE CAPE/HELICITY EXISTS TO
WARRANT A CHANCE OF SEVERE STORMS...ALTHOUGH DIURNAL COOLING WILL
AND SLIGHT CHILLED INSHORE SST VALUES COULD OFFSET INCREASING
CONVECTIVE INTENSITY TRENDS.

NEXT NOTEWORTHY ITEM...PRECEDING THIS SEVERE POTENTIAL PLENTY
STRATIFORM RAIN APPEARS LIKELY...AND THE LATEST WPC QPF FORECAST
FOR SUNDAY AND MONDAY PAINTS 1.5-2.5 INCHES OF RAIN FOR OUR AREA
FOR THE 2-DAY PERIOD. STRATIFORM WILL TRANSITIONS TO CONVECTION AS
THE WARM FRONT LIFTS NORTH OF THE AREA INTO EARLY MONDAY.

EXCEPTIONALLY MILD MONDAY WITH MAXIMUM TEMPERATURES WELL INTO THE
70S IN A DEEP AND MOIST SW WIND FLOW ATOP THE AREA...AND FROPA
NEAR END OF THE PERIOD PRIOR TO DAYBREAK TUESDAY. COOLEST PORTION
OF PERIOD DAYBREAK SUNDAY WITH CLOUDS AND MIDDLE 40S. HIGHEST POP
VALUES SUNDAY NIGHT.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
AS OF 336 PM SATURDAY...LINGERING FRONT STALLED OFF THE EAST COAST
TUE  INTO WED AND SHORTWAVE DROPPING INTO THE WESTERN GULF WILL
BRING RAIN TO THE AREA DURING THE MIDDLE OF NEXT WEEK. WEAK
SURFACE WAVE DEVELOPING ON THE BOUNDARY OVER SOUTHERN FL EARLY TUE
WILL BE ENHANCED BY THE AFOREMENTIONED SHORTWAVE. AS THE LOW
TRACKS NORTHEAST ALONG THE FRONT...JUST OFF THE SE COAST...RAIN
WILL SPREAD OVER MUCH OF THE CAROLINAS. WED LOOKS AS THOUGH IT
COULD BE A MISERABLE DAY WITH THE FORECAST AREA ON THE COOL SIDE
OF THE LOW AND PERIODS OF HEAVY RAIN POSSIBLE. HIGHS WED MAY STAY
IN THE MID 40S WITH AROUND 50 ALONG THE COAST AND HAVE TRENDED
HIGHS DOWN.

RAPID DRYING WILL COMMENCE LATE WED INTO WED NIGHT AS 5H TROUGH
AXIS  LIFTS NORTHEAST AND DEEP DRY AIR ARRIVES. BY THU AM
PRECIPITABLE WATER VALUES WILL BE AROUND 0.40 INCH AND SOUNDINGS
SHOW STRONG DOWNWARD MOTION. LATER HALF OF THE PERIOD REMAINS A
QUESTION WITH LATEST GFS/ECMWF DISAGREEING ON THE
STRENGTH/AMPLITUDE OF THE NEXT MID LEVEL TROUGH. GFS DEVELOPS
ZONAL FLOW ALOFT FRI/SAT WHILE THE ECMWF MAINTAINS 5H TROUGHING
INTO THE START OF THE WEEKEND. BOTH SOLUTIONS WOULD RESULT IN A
DRY FORECAST BUT WITH DIFFERENCES IN TEMPERATURES AND POSSIBLY
AFTERNOON CLOUD COVER. GFS ENSEMBLES ARE NOT VERY HELPFUL WITH
ROUGHLY AN EQUAL SPLIT BETWEEN THE 2 SOLUTIONS. INHERITED FORECAST
IS BASICALLY A BLEND OF THE GFS/ECMWF AND WILL CONTINUE WITH THIS
THINKING UNTIL THERE IS BETTER AGREEMENT.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AS OF 00Z...EXPECT VFR OVERNIGHT INTO THE MORNING HOURS ON
SUNDAY...WITH CONDITIONS GRADUALLY DETERIORATING TO MVFR AND THEN
IFR TOWARDS THE END OF THE PERIOD AS LOW CIGS AND SHRA/ISOLATED TSRA
ACCOMPANY THE NEXT APPROACHING WEATHER SYSTEM.

LIGHT WINDS WITH INCREASING HIGH CLOUDS WILL BE ON TAP FOR TONIGHT
AND THROUGH THE MORNING HOURS AHEAD OF THE NEXT APPROACHING WEATHER
SYSTEM. AS A RESULT...EXPECT VFR TO PREVAIL. ON SUNDAY...LOW TO MID
CLOUDS WILL SLOWLY INFILTRATE INTO THE AREA BY LATE MORNING...WITH
INCREASING CHANCES FOR RAIN THROUGHOUT THE DAY. HEAVY RAIN AT TIMES
AND LOWER CIGS WILL CREATE DETERIORATING CONDITIONS TO MVFR AND
EVENTUALLY IFR TOWARDS SUNDAY EVENING. THERE IS A POSSIBILITY OF
THUNDERSTORMS INTO THE EVENING HOURS...BUT GIVEN LOWER CONFIDENCE OF
TIMING AND WHILE CONTINUING TO MONITOR LATEST GUIDANCE
INFORMATION...HAVE OPTED TO NOT INTRODUCE ATTM. AS FOR
WINDS...EXPECT NORTHEAST WINDS TO BECOME SOUTHEAST BY THE
AFTERNOON/EVENING HOURS...WITH SUSTAINED WINDS AOB 10 KTS.

EXTENDED OUTLOOK...UNSETTLED WEATHER IS EXPECTED POSSIBLY THROUGH
TUESDAY...WITH OCCASIONAL SHOWERS AND MVFR/IFR CONDITIONS. VFR
TUESDAY AFTERNOON WITH POSSIBLE MVFR CONDITIONS WEDNESDAY. VFR
THURSDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 940 PM SATURDAY...NO SIGNIFICANT CHANGE ARE NEEDED TO THE
FORECAST LATE THIS EVENING. OBSERVATIONS SHOW VEERING WINDS ACROSS
THE WATERS...MAINLY E TO NE ALONG THE BEACHES WITH SE WINDS OUT AT
THE FRYING PAN SHOALS BUOY. THE WARM FRONT SHOULD MAKE RAPID
PROGRESS TOWARD THE BEACHES OVERNIGHT WITH RISING TEMPERATURES
EXPECTED. FORTUNATELY THE MASSIVE INCREASE IN WIND SPEEDS WILL HOLD
OFF UNTIL DURING THE DAY SUNDAY. SEAS 2-3 FEET (LOCALLY 4 FEET IN
THE OUTER PORTION OF THE COASTAL WATERS) SHOULD CONTINUE THROUGH THE
NIGHT.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 336 PM SATURDAY...DETERIORATING MARINE CONDITIONS SUNDAY AS SE
WINDS CRANK UP TO 15-25 KT AHEAD OF AN APPROACHING WARM FRONT. S
AND SW BLUSTERY FLOW TO FOLLOW FOR MONDAY 15-25 KT...WHILE SEAS
PEAK MAINLY SUNDAY NIGHT DURING MAXIMUM IN S-SE WIND OFFSHORE OF
6-10 FEET AND HIGHEST OUTER WATERS. STRONG TO SEVERE THUNDERSTORMS
POSSIBLE SUNDAY NIGHT THROUGH MONDAY...GULF STREAM LATE MONDAY.
VENTURING OFFSHORE IS DISCOURAGED FOR SMALL CRAFT VESSELS SUNDAY AND
MONDAY.

LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 336 PM SATURDAY...FRONT STALLED OFF THE COAST TUE WILL HELP
MAINTAIN LIGHT NORTHERLY FLOW. LOW PRESSURE DEVELOPING ON THE FRONT
LATE TUE WILL TRACK NORTHEAST WED...PASSING JUST EAST OF THE WATERS.
AS THE LOW DEVELOPS THE GRADIENT WILL TIGHTEN UP WITH SPEEDS
INCREASING TO 20 TO 25 KT WED. LOW EXITS NORTHEAST WED NIGHT WITH
WINDS BACKING TO WESTERLY AS THE LOW EXITS. GRADIENT DECREASES WITH
SPEEDS DROPPING TO 10 TO 15 KT BY THU MORNING. SEAS 2 TO 3 FT ON TUE
WILL BUILD TO 4 TO 7 FT LATE WED IN RESPONSE TO INCREASED NORTHERLY
FLOW. DEVELOPMENT OF OFFSHORE FLOW BEHIND THE EXITING LOW DROPS SEAS
TO 2 TO 4 FT WED NIGHT AND AROUND 2 FT THU.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...

SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM SUNDAY TO 6 AM EST TUESDAY
         FOR AMZ250-252-254-256.

&&

$$

SYNOPSIS...MJC
NEAR TERM...TRA
SHORT TERM...MJC
LONG TERM...III
AVIATION...SGL





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