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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 211922
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
320 PM EDT MON JUL 21 2014

.SYNOPSIS...
A STATIONARY FRONT STALLED ACROSS THE INTERIOR CAROLINAS WILL SLOWLY
DISSIPATE TONIGHT AND TUESDAY. BERMUDA HIGH PRESSURE WILL BUILD INTO
THE AREA WEDNESDAY AND THURSDAY. A COLD FRONT WILL APPROACH FROM THE
NORTHWEST LATE IN THE WEEK AND STALL NORTH OF THE AREA FOR THE
WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM MONDAY...THIS IS CERTAINLY AN ATYPICAL SUMMER WEATHER
PATTERN ACROSS THE CAROLINAS. AN UPPER LEVEL LOW ACROSS WESTERN
GEORGIA AND THE UPPER CENTER OF THE BERMUDA RIDGE WELL OFFSHORE ARE
DIRECTING A STREAM OF RICH TROPICAL MOISTURE NORTH ACROSS THE AREA.
PRECIPITABLE WATER VALUES ARE IN EXCESS OF 2.1 INCHES WITH THIS
MORNING`S 12Z CHS SOUNDING SHOWING 2.23 INCHES...NEAR THE 95TH
PERCENTILE FOR JULY. A STATIONARY FRONT WAS RATHER DIFFUSE EARLY
THIS MORNING BUT HAS BECOME RENEWED BY COOL CONVECTIVE OUTFLOW AND
IS NOW LOCATED FROM NEAR CAPE FEAR TO CONWAY TO SOUTHERN FLORENCE
COUNTY. THIS HAS BEEN THE FOCUS FOR NEW CONVECTIVE DEVELOPMENT WITH
THE ENVIRONMENTAL SOUTH FLOW ADVECTING RAIN BACK OVER THE COLD DOME.
THIS WILL PROBABLY CONTINUE FOR THE NEXT FEW HOURS UNTIL INSTABILITY
GETS USED UP.

HEAVY RAIN HAS BEEN THE BIG STORY TODAY. RADAR ESTIMATED TOTALS HAVE
REACHED 4+ INCHES NEAR WILMINGTON...JUST NORTH OF CONWAY...AND
ACROSS NE FLORENCE COUNTY INTO CENTRAL DILLON COUNTY. FLOODING
REPORTS HAVE SO FAR BEEN OF THE MINOR VARIETY BUT THAT MAY CHANGE AS
TOTALS CONTINUE TO INCREASE. THE ONLY INGREDIENT MISSING FOR A MORE
WIDESPREAD FLOOD EVENT IS STRONGER 5000-10000 FOOT WIND SPEEDS.
WINDS ARE GENERALLY LESS THAN 10 KNOTS THROUGH THIS LAYER.

CONSIDERABLE CONVECTIVE DEBRIS CLOUDINESS IN THE EVENING WILL SLOWLY
DECAY OVERNIGHT...ALTHOUGH ANY SIGNIFICANT CLEARING WILL PROBABLY
JUST RESULT IN THE DEVELOPMENT OF LOW STRATUS JUST OFF THE SURFACE.
LOWS SHOULD FALL INTO THE 70-73 DEGREE RANGE...WARMEST AT THE
BEACHES.

RECORD RAINFALL TOTALS FOR TODAY:
WILMINGTON   3.84 INCHES IN 1939   (2.48 INCHES TODAY AS OF 315 PM)
FLORENCE     1.70 INCHES IN 1995   (1.14 INCHES TODAY AS OF 315 PM)

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...DEEP MOISTURE SHOULD CONTINUE TO BE CHANNELED
INTO THE COASTAL CAROLINAS ON TUESDAY. DEEPENING UPPER LOW TO OUR
WEST WILL BE RETROGRADING SLIGHTLY WHILE RIDGE OFFSHORE BUILDS
SLIGHTLY. MODELS SHOW LONG FETCH SOUTHERLY FLOW AT THE SURFACE WITH
A COASTAL TROUGH EARLY IN THE DAY THAT MIGRATES INLAND AS THE DAY
WEARS ON. THE WRF IN PARTICULAR IMPLIES THAT CONVECTIVE COVERAGE AND
QPF PROSPECTS MAY MIRROR THOSE OF TODAY WITH FORECAST PRECIPITABLE
WATERS STAYING AS ELEVATED AS THEY ARE NOW OR EVEN INCREASING
SLIGHTLY TO 2.25" AND ALTHOUGH THE STRONGER MID LEVEL VORTS
PORTRAYED IN THE WRF HAVE THE LOOK OF CONVECTIVE FEEDBACK ANALYSIS
OF LOW LEVEL POTENTIAL VORTICITY FIELDS SHOW NO SPURIOUS DATA TO
INDICATE SUCH. WEDNESDAY IS A BIT OF A TRANSITIONAL DAY...BUT COULD
READILY SEE HOW THE AFTERNOON OFFERS UP HIGHER THAN NORMAL COVERAGE
OF STORMS ALBEIT LESSER THAN TODAY/TUESDAY. THE MAIN UPPER LOW TO
OUR WEST CONTINUES TO RETROGRADE BUT WE STILL HAVE A MID LEVEL
SOUTHERLY COMPONENT...USUALLY A GOOD INDICATOR FOR AN  ACTIVE
DAY...ESPECIALLY WITH LITTLE IMPETUS FOR LOW LEVELS TO DRY OUT MUCH.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/....
AS OF 300 PM MONDAY...LONGWAVE TROUGH EXPANDING ACROSS THE EAST WILL
CAPTURE A RETROGRADING CLOSED 500MB LOW OVER THE GULF COAST LATE IN
THE WEEK...AND SWING IT BACK TO THE NORTHEAST. THIS WILL LEAVE BROAD
TROUGHING ACROSS THE EAST THROUGH THE WKND. BENEATH THIS TROUGH...A
COLD FRONT WILL DROP SLOWLY SOUTHEAST...REPLACING THE HIGH PRESSURE
RIDGE THAT WILL BE OVER THE AREA FROM MID-WEEK. WITH STRONG MOIST
ADVECTION AHEAD OF THIS BOUNDARY...AND WAVES OF LOW PRESSURE
EXPECTED TO DEVELOP ALONG IT...THU/FRI SHOULD ONCE AGAIN FEATURE
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS...WITH TEMPS AROUND
CLIMO BOTH DAYS. THE COLD FRONT DRIFTS OFFSHORE FOR THE
WKND...LEAVING A DRIER COLUMN...BUT STILL TYPICAL SUMMERTIME
CONVECTION CHANCES AND TEMPS JUST BELOW NORMAL. BEYOND THE WEEKEND
DURING EARLY NEXT WEEK...SIGNALS POINT TO A STRONG RE-AMPLIFICATION
OF THE MID-LEVEL PATTERN WITH AN ANOMALOUSLY DEEP TROUGH ACROSS THE
EAST. THIS COULD BRING A RENEWED PERIOD OF BELOW NORMAL TEMPS AND
ABOVE NORMAL PRECIP CHANCES BEGINNING MONDAY.

&&

.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 18Z...WITH PRECIPITABLE WATER AMOUNTS OVER TWO INCHES AND
INSTABILITY AS HIGH AS 2500 J/KG...LOOK FOR CONVECTION WITH HEAVY
RAIN TO FIRE ALL AFTERNOON AND A BIT INTO THE EVENING HOURS. THINGS
WILL BEGIN TO CALM DOWN BY 02Z AS INSTABILITY DROPS OFF
SIGNIFICANTLY. WITH ALL THE HEAVY RAIN...FOG IS A POSSIBILITY...
HOWEVER CONVECTIVE DEBRIS CLOUDINESS SHOULD KEEP IT AT MVFR. MVFR
CEILINGS ARE ALSO LIKELY GIVEN THE REMAINING LOW LEVEL MOISTURE.
TUESDAY...ANOTHER ROUND OF CONVECTION MUCH LIKE TODAY...BEGINNING
FAIRLY EARLY DUE TO LARGE MOISTURE VALUES AND NO CAPPING INVERSION
ALOFT.

EXTENDED OUTLOOK...CHANCE OF SHOWERS/TSTMS PERSISTS THROUGH THE
EXTENDED FRIDAY. EXPECT PREDOMINANTLY VFR CONDITIONS WITH BRIEF
PERIODS OF MVFR CIGS/VSBYS IN STORMS. VFR SATURDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM MONDAY...A STATIONARY FRONT HAS BEEN RENEWED BY A LARGE
AREA OF SHOWER AND THUNDERSTORM ACTIVITY NORTH OF CAPE FEAR AND
INLAND...AND THE BOUNDARY APPEARS TO LIE ALONG THE COAST OF
BRUNSWICK COUNTY AT THE TIME OF THIS WRITING. EAST-NORTHEAST WINDS
NORTH OF THE FRONT CONTRAST WITH A MORE SOUTHEASTERLY FLOW DOWN TO
THE SOUTH. THE BOUNDARY IS EXPECTED TO SINK SOUTH THROUGH THE GRAND
STRAND LATER THIS EVENING WITH A GENERALLY EAST-NORTHEAST WIND
THROUGH THE OVERNIGHT HOURS. OUTSIDE OF THUNDERSTORMS WINDS SHOULD
AVERAGE 10 KNOTS OR LESS...ALTHOUGH WE SEE WINDS GUSTING AS HIGH AS
15-20 KNOTS CURRENTLY AT WRIGHTSVILLE BEACH AND SOUTHPORT DUE TO
THUNDERSTORM ACTIVITY IN THE AREA.

SEAS CONSIST LARGELY OF A SOUTHEASTERLY 7-8 SECOND SWELL...WITH A
NORTHEAST CHOP ON TOP NORTH OF CAPE FEAR. COMBINED SEAS ARE
AVERAGING 3 FEET WITH SOME 2-FOOTERS NEAR SHORE SOUTH OF CAPE FEAR.
LITTLE CHANGE IS ANTICIPATED THROUGH THE NIGHT.

SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...TUESDAY BRINGS A PREDOMINANTLY SOUTHEASTERLY
WIND AS A SURFACE TROUGH INITIALLY NEAR THE COAST MOVES INLAND WHILE
WEST ATLANTIC HIGH PRESSURE REMAINS NEARLY STATIONARY. SPECTRAL WAVE
BULLETINS SHOW THAT A GENERAL 3 FT DOMINANT SEA STATE TO BE A NEARLY
SINGULAR 7 SECOND WAVE SET. A MORE TYPICAL PIEDMONT TROUGH SETS UP
ON THURSDAY AND THE ATLANTIC HIGH DOES APPEAR TO FLEX WESTWARD
CLOSER TO THE COAST A BIT. THIS SHOULD BE GOOD FOR ABOUT A 5KT
INCREASE IN THE RANGE OF WAVE HEIGHTS AND SHOULD INTRODUCE A 4 FT
WIND WAVE TO MOST ZONES.

LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 300 PM MONDAY...PINCHED GRADIENT BETWEEN OFFSHORE HIGH
PRESSURE AND A SLOWLY APPROACHING COLD FRONT FROM THE NW WILL DRIVE
SW WINDS UP TO 15-20 KTS THURSDAY AND MUCH OF FRIDAY. THIS FRONT IS
EXPECTED TO CROSS OVER THE WATERS VERY LATE FRIDAY WITH A WIND SHIFT
TO THE WEST...AND A SPEED REDUCTION TO LESS THAN 10 KTS. THIS WILL
BE SHORT LIVED HOWEVER...AS THE FRONT PUSHES BACK TO THE NORTH BY
THE END OF THE PERIOD WITH A RETURN OF SW WINDS. SEAS THU/FRI WILL
RISE TO 4-5 FT AT TIMES THANKS TO THESE STRONGER WINDS AND A SE
GROUND SWELL...AND CAUTIONARY STATEMENTS MAY BE REQUIRED. THE WATERS
WILL FEATURE LOWER AMPLITUDE SEAS ON SATURDAY OF 2-3 FT.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR NCZ106-108.

MARINE...NONE.

&&

$$
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...JDW
AVIATION...43/TRA