Area Forecast Discussion
Issued by NWS Wilmington, NC

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000
FXUS62 KILM 011054
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
655 AM EDT SAT NOV 1 2014

.SYNOPSIS...
A POTENT LOW PRESSURE SYSTEM WILL PUSH A STRONG COLD FRONT THROUGH
THE CAROLINAS THIS MORNING BEFORE RAPIDLY INTENSIFYING AS IT
PASSES THROUGH THE AREA AND OFF SHORE THROUGH TONIGHT. COLD
CANADIAN HIGH PRESSURE WILL BUILD IN BEHIND IT...BRINGING GUSTY
NORTHERLY WINDS AND THE COLDEST TEMPERATURES OF THE SEASON THROUGH
THIS WEEKEND. TEMPERATURES WILL MODERATE MONDAY INTO THE MIDDLE OF
NEXT WEEK AS HIGH PRESSURE MOVES SLOWLY OFFSHORE.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 6:30 AM SATURDAY...SOME SURPRISINGLY STRONG CONVECTION
MOVING ACROSS NEW HANOVER COUNTY THIS MORNING BUT ELSEWHERE
ACTIVITY IS NIL. FORECAST REMAINS UNCHANGED WITH LATEST UPDATE.
PREVIOUS DISCUSSION FOLLOWS:

A BROAD AREA OF LOW PRESSURE OVER THE EASTERN CAROLINAS WILL
CONSOLIDATE AS THE LOW CENTER DEEPENS AND SWINGS A POWERFUL COLD
FRONT OFFSHORE. THE COMBINATION OF STRONG COLD
ADVECTION...EXTENSIVE CLOUD COVER AND FREQUENT PERIODS OF RAIN
WILL LEAD TO VERY UNSEASONABLY COLD DAYTIME TEMPERATURES. THERE IS
A GOOD POSSIBILITY THAT WE COULD BREAK RECORD LOW-HIGH
TEMPERATURES FOR TODAY DEPENDING UPON HOW THINGS SHAKE OUT...WITH
SOME PLACES PERHAPS NOT BREAKING OUT OF THE 40S. SEQUENCE OF EVENT
MEANS MOST IF NOT ALL LOCATIONS WILL SEE THEIR MAXIMUM
TEMPERATURES FOR THE DAY REACHED THIS MORNING...WITH READING FLAT-
LINING OR DECREASING DURING THE AFTERNOON. BASED ON PAST
EXPERIENCE WITH SIMILAR SITUATIONS HAVE STAYED ON THE LOW END OF
GUIDANCE FOR TODAYS HIGH TEMPERATURES. AS WOULD BE
EXPECTED...STRONG WINDS WILL FOLLOW FROPA...BUT A CONSENSUS OF
GUIDANCE INDICATES AN ADVISORY FOR WINDS IS NOT NEEDED.

HAVE MAINTAINED 100 PERCENT FOR POPS TODAY. ALTHOUGH AVAILABLE
MOISTURE IS ON THE ANEMIC SIDE WITH P/W VALUES TOPPING OUT ONLY IN
THE 0.75 INCH RANGE...THE DYNAMICS OF THE RAIN-MAKING PROCESSES WILL
BE SO EFFICIENT AND POWERFUL THAT SHOWERS ARE A CERTAINTY. A FEW
LIGHTNING STRIKES ARE ALSO POSSIBLE...BUT WILL NOT BE PERVASIVE.
LOW FREEZING LEVELS WHEN COMBINED WITH THE STRONG DYNAMICS ALSO
MEANS THAT SLEET/GRAUPEL CAN NOT BE RULED OUT THIS AFTERNOON. AS
CONFIDENCE IN THIS SCENARIO IS NOT AS HIGH AS I WOULD LIKE IT TO BE
FOR MENTION OF FROZEN PRECIP...WILL KEEP IT OUT OF THE FORECAST FOR
NOW.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 330 AM SATURDAY...WINTER-LIKE WEATHER TO START OFF THE WEEK.
POTENT LOW PRESSURE SYSTEM OVER NEW ENGLAND COAST WILL BE LIFTING
OFF TO THE NORTHEAST WHILE HIGH PRESSURE BUILDS IN BEHIND IT
THROUGH SUNDAY INTO MONDAY. TIGHTENED GRADIENT EARLY SUNDAY WILL
RELAX THROUGH THE DAY INTO MONDAY AS HIGH PRESSURE SHIFTS CLOSER
OVERHEAD. THEREFORE ANY GUSTY NORTHERLY WINDS THAT MIX DOWN ON
SUNDAY WILL DIMINISH THROUGH THE DAY LEAVING NEAR CALM WINDS BY
MONDAY MORNING. ANY LINGERING LOW LEVEL MOISTURE OR CLOUDS EARLY
SUNDAY WILL CLEAR OUT IN PLENTY OF DRY AIR AND SUBSIDENCE ON THE
BACK END OF THE LOW THROUGH SUNDAY. EXPECT PLENTY OF SUNSHINE
AROUND BY SUNDAY AFTN...BUT WITH SUCH A COLD AIR MASS IN PLACE AND
TEMPS STARTING OUT BELOW 40 MOST PLACES...HIGHS WILL ONLY MAKE IT
INTO THE MID 50S MOST PLACES. THIS COULD LEAD TO SOME RECORD LOW
MAX TEMPS WHICH ARE GENERALLY BETWEEN 55 AND 60 AROUND THE
FORECAST AREA. DEWPOINT TEMPS WILL BE IN THE 20S MOST PLACES SUN
AFTN.

A MID TO UPPER RIDGE WILL BUILD IN BEHIND DEPARTING TROUGH IN A
HIGHLY AMPLIFIED PATTERN. THIS WILL ALLOW SOME RAPID HEIGHT RISES
UP TO 30 DEM THROUGH SUNDAY INTO MONDAY. LOW LEVEL THICKNESSES AND
850 TEMPS WILL BE ON THE RISE. 850 TEMPS DOWN AS LOW AS -3 TO 4C
SUN MORNING WILL RISE ABOUT 10 DEGREES BY MON AFTN. OVERALL EXPECT
AIR MASS TO BEGIN TO MODIFY THROUGH MONDAY...BUT WITH NEAR CALM
WINDS AND COLD AND DRY HIGH PRESSURE IN PLACE SUN NIGHT...TEMPS
WILL BE DOWN BELOW OR NEAR FREEZING IN MANY PLACES INLAND. A
FREEZE WATCH HAS BEEN ISSUED FOR ALL COUNTIES EXCEPT COASTAL
COUNTIES. ALSO MAY SEE SOME FROST IN PLACES BUT MOISTURE MAY BE
LACKING TO PRODUCE ANYTHING MORE THAN PATCHY FROST. EVEN WITH A
LARGE REBOUND IN TEMPS...EXPECT HIGH TEMPS ON MONDAY TO REMAIN
BELOW NORMAL...IN THE MID 60S MOST PLACES UNDER FULL SUNSHINE.

HIGH PRESSURE ALMOST DIRECTLY OVERHEAD WILL PRODUCE IDEAL
RADIATIONAL COOLING CONDITIONS MON NIGHT. THEREFORE EXPECT TEMPS
TO DROP OFF RAPIDLY AFTER SUNSET ONCE AGAIN MON EVE BACK DOWN
BELOW 40 DEGREES MOST PLACES INLAND OF THE COAST.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 330 AM SATURDAY...HIGH PRESSURE FROM THE SURFACE UP THROUGH
THE MID TO UPPER LEVELS OF THE ATMOSPHERE WILL SLOWLY LOSE ITS
GRIP OVER THE CAROLINAS THROUGH MID WEEK. HIGH PRESSURE WILL
INITIALLY BE OVERHEAD TUES MORNING BUT WILL SHIFT SLOWLY OFF SHORE
BY TUES NIGHT WITH A WEAK RETURN FLOW SETTING UP. THIS WILL ALLOW
AIR MASS TO MODIFY WITH DEWPOINT TEMPS JUMPING UP A GOOD 10
DEGREES FROM TUES TO WED. TEMPS WILL REBOUND TO ABOVE NORMAL WITH
READINGS IN THE MID 70S THROUGH MID WEEK WITH PLENTY OF SUNSHINE
AS RIDGE PROVIDES PLENTY OF SUBSIDENCE AND DRY AIR.

BY LATE WED THE NEXT MID TO UPPER TROUGH WILL REACH DOWN FROM THE
GREAT LAKES AS IT MOVES EAST. THIS WILL PUSH A COLD FRONT THROUGH
THE CAROLINAS ON THURS BUT LOOKS MOISTURE STARVED AT THIS
POINT...WITH MAINLY SOME CLOUDS IN THE FORECAST FOR THURS. THE
MAIN IMPACT OF THIS FRONT WILL BE TO KNOCK TEMPS BACK DOWN BELOW
NORMAL FOR FRIDAY.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 12Z...THIS IS ONE CRAZY WEATHER SYSTEM! THE TEMP IS 49 DEGREES
AND WE HAVE REPORTS OF THUNDER AND HAIL. SOUTHPORT HAD PEA SIZE HAIL
COVERING THE GROUND. THERE IS SOME SERIOUS FORCING GOING ON. MOST OF
THE HEAVY CONVECTION WILL ROTATE THROUGH PENDER COUNTY AND OUT OF
THE REGION BY 13Z. UPPER COLD CORE WILL ROTATE SOUTH OF THE REGION
WITH SURFACE LOW NEARLY OVERHEAD. ONCE THE SURFACE LOW MOVES
EAST...WINDS WILL SHIFT NORTHWESTERLY AND INCREASE AS STRONG MIXING
BEGINS. A BAND OF HEAVY RAIN IS POSSIBLE THIS AFTERNOON WITH THE
WRAP AROUND MOISTURE ON THE BACK SIDE OF THE LOW. WINDS IN THE
CONVECTION WILL BE ENHANCED. THIS EVENING...RAIN SUBSIDING BUT THE
GRADIENT WILL STILL BE STRONG WITH NORTHWEST WINDS POSSIBLY GUSTING
OVER 35 KTS. CEILINGS WILL LIKELY BOUNCE AROUND FROM MVFR TO IFR AT
TIMES THIS AFTERNOON.

EXTENDED OUTLOOK...BREEZY TO WINDY CONDITIONS TO PERSIST INTO SUNDAY
AFTER LOW PRESSURE STRENGTHENS OFF THE CAROLINA COAST...AND
ACCELERATES TO THE NE. VFR FOR MONDAY AND TUESDAY AS THE CENTER OF
STRONG HIGH PRESSURE MOVES OVERHEAD. LIGHT MORNING FOG POSSIBLE
WEDNESDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 6:30 AM SATURDAY...FORECAST REMAINS UNCHANGED WITH LATEST
UPDATE. PREVIOUS DISCUSSION FOLLOWS:

STRONG NORTHWESTERLY WINDS WILL FOLLOW THE PASSAGE OF A POWERFUL
COLD FRONT LATER TODAY. KEEPING A GALE WARNING IN EFFECT FOR THIS
AFTERNOON AND TONIGHT FOR GUSTS UPWARDS OF 35 KTS. OFFSHORE FETCH
WILL LIMIT SEAS TO 5 TO 7 FT. UNTIL THEN...WINDS AND SEAS THIS
MORNING REMAIN DECEPTIVELY BENIGN AS A BROAD AREA OF LOW PRESSURE
EXTENDS ACROSS THE EASTERN CAROLINAS. ONE SHOULD NOT BE FOOLED BY
THIS THOUGH...AS CONDITIONS WILL RAPIDLY DETERIORATE...BECOMING
QUITE DANGEROUS THIS AFTERNOON AND OVERNIGHT.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 330 AM SATURDAY...POTENT LOW PRESSURE SYSTEM OVER NEW
ENGLAND COAST WILL BE LIFTING OFF TO THE NORTHEAST WHILE HIGH
PRESSURE BUILDS IN BEHIND IT THROUGH SUNDAY INTO MONDAY. THE
TIGHTENED GRADIENT FLOW BETWEEN THESE TWO SYSTEMS WILL PRODUCE
N-NW WINDS 15 TO 25 KTS SUNDAY MORNING BEFORE IT BEGINS TO RELAX
AND DIMINISH THROUGH LATE SUNDAY INTO MONDAY. SEAS ABOVE 6 FT SUN
MORNING WILL BEGIN TO DROP...DOWN BELOW SCA CONDITIONS BY SUN
EVENING.

AS HIGH PRESSURE SHIFTS CLOSER OVERHEAD THROUGH MONDAY...WINDS
WILL CONTINUE TO DIMINISH AS THEY BACK AROUND TO THE N-NW DROPPING
BELOW 10 KTS BY MON EVE. SEAS WILL FALL OFF TO 2 TO 4 FT BY MON
MORNING AND DOWN BELOW 3 FT BY MON EVENING.

LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 330 AM SATURDAY...A QUIET TIME FOR MARINE WEATHER TUES INTO
WED AS HIGH PRESSURE OVERHEAD SHIFTS SLOWLY EAST. WINDS WILL
BECOME VERY LIGHT AND SLIGHTLY MORE VARIABLE AS THEY COME AROUND
FROM THE NW TO THE SW. SEAS WILL BE BELOW 2 FT THROUGH MOST OF THE
PERIOD WITH A SLIGHTLY LONGER PERIOD...UP TO 9 SEC SWELL DOMINATING.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...FREEZE WATCH LATE SUNDAY NIGHT FOR SCZ017-023-024-032-033-039-
     053-055.

NC...FREEZE WATCH LATE SUNDAY NIGHT FOR NCZ087-096-099-105-107-109.

MARINE...GALE WARNING FROM NOON EDT TODAY TO 6 AM EST SUNDAY FOR AMZ250-
     252-254-256.

&&

$$

SYNOPSIS...RGZ
NEAR TERM...REK
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...43
MARINE...REK/RGZ







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