National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 310539
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
139 AM EDT THU JUL 31 2014

.SYNOPSIS...
-- Changed Discussion --
FAIR WEATHER WILL CONTINUE THROUGH THURSDAY AS CANADIAN HIGH
PRESSURE SETTLES ACROSS THE AREA. A COASTAL FRONT WILL LIFT NORTH
ACROSS THE AREA FRIDAY AND INTO THE WEEKEND...BRINGING GOOD RAIN
CHANCES INTO EARLY NEXT WEEK.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
-- Changed Discussion --
AS OF 1:30 PM THURSDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. RELEVANT PORTION OF PREVIOUS DISCUSSION FOLLOWS:

A CLOSED LOW AT 500 MB BETWEEN THE GREAT LAKES AND HUDSON BAY IS
MAINTAINING A LONGWAVE TROUGH OVER EASTERN NORTH AMERICA. OBSERVED
850 MB TEMPERATURES OF +14 TO +15C ARE A FEW DEGREES BELOW NORMAL
TOO...AND TODAY`S HIGH TEMPERATURES WERE ANYWHERE FROM 2 TO 5
DEGREES BELOW NORMAL FOR THE DATE.

A STALLED FRONT EXTENDING FROM NEAR THE FLORIDA GEORGIA LINE TO
THE GULF STREAM WATERS OFF SOUTH CAROLINA MARKS THE EDGE OF
TROPICAL AIR AT THE SURFACE. OUR AIRMASS IS HEAVILY MODIFIED
CONTINENTAL POLAR AIR THAT HAS SPENT THE PAST DAY TRAVERSING THE
SEASONABLY WARM WATER OFF THE MID-ATLANTIC COAST. WHILE CONVECTIVE
CLOUDINESS SHOULD DIMINISH OVERNIGHT MODELS ARE SHOWING FAIRLY
GOOD CHANCES FOR CLOUDS REMAINING AT LEAST ACROSS THE SC PEE DEE
REGION...POTENTIALLY SPREADING EASTWARD TO NEAR THE COAST AS WELL.
WEAK ISENTROPIC LIFT DEVELOPING NEAR THE BASE OF THE SUBSIDENCE
INVERSION ALOFT SHOULD INGEST A FEED OF ATLANTIC MOISTURE MOVING
ONTO THE GEORGIA AND SOUTH CAROLINA COAST...LIFTING IT UP THROUGH
THE 800-750 MB LAYER OVERNIGHT. THE LIFT IS QUITE WEAK AND WERE IT
NOT FOR ITS RICH MOISTURE CONTENT IT PROBABLY WOULD NOT BE WORTH
MENTIONING. I HAVE INCREASED CLOUD COVER FORECASTS ALONG THE I-95
CORRIDOR OVERNIGHT AS A RESULT.

LOW TEMPERATURES SHOULD STILL REACH THE UPPER 60S FOR MOST
INTERIOR LOCATIONS...WITH 70-75 EXPECTED AT THE COAST IN AN
ONSHORE FLOW.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...EXPECT TEMPERATURES TO BE SLIGHTLY BELOW
NORMAL THROUGH THE PERIOD. H5 TROF ACROSS HUDSON BAY IN CANADA
STARTS TO LIFT TO THE NE TURNING THE UPPER LEVEL FLOW FROM NW
AROUND TO THE SW BY FRIDAY AND A WARM MOIST TRANSPORT OF AIR IS
ADVECTED INTO THE REGION BUT THIS WILL BE OFFSET AS COASTAL TROUGH
PUSHES ONSHORE DURING FRIDAY AND INCREASED CLOUD COVER AND POPS
WILL HELP TO KEEP TEMPS AGAIN SLIGHTLY BELOW NORMAL. ON THURSDAY
REGION STARTS TO SEE AN INCREASE IN PWAT AT THIS TIME I HAVE
SCALED BACK ON THE THREAT OF ANY PRECIPITATION UNTIL THE NIGHT
TIME WITH A BETTER CHANCE BY FRIDAY. HAVE TAKEN A BLEND OF THE
NAM/GFS SOLUTION FOR TEMPS/POP BUT HAVE FAVORED THE HIGHER POPS
FROM THE GFS ON FRIDAY AS INCREASED MOISTURE TRANSPORT INTO THE
REGION AHEAD OF COASTAL TROF MOVING ONSHORE SHOULD ENHANCE
PRECIPITATION THREAT ACROSS REGION. THIS WILL ALSO HELP IN KEEPING
TEMPS BELOW NORMAL ACROSS THE REGION AGAIN. PWAT INCREASE ON
FRIDAY TO AROUND 2 INCHES ALONG WITH UPPER LEVEL DYNAMICS TO
INCREASE POPS TO OVER 40 PERCENT BY AFTERNOON.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...UPPER TROUGH AXIS TO OUR WEST SATURDAY AND
SUNDAY WHILE SURFACE BOUNDARY SLOWLY PUSHES INLAND. STAGE IS SET
FOR SOME FAIRLY WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY WHILE
CLOUD COVER INHIBITS DAYTIME HIGHS FROM REACHING CLIMO NORMS. MID
LEVEL TROUGH AND SURFACE BOUNDARY BOTH WASH OUT AS MONDAY
PROGRESSES BUT THERE STILL SHOULD BE ENOUGH DEEP SOUTHWESTERLY
FLOW FOR A SIMILAR FORECAST. TUESDAY HAD PREVIOUSLY LOOKED LIKE A
MORE TYPICAL AUGUST DAY BUT MODELS ARE A LITTLE SLOWER WITH THE
MID LEVEL VEERING AND STILL SHOW SOME WEAK VORTICITY CENTERS
PASSING OVERHEAD. FEEL IT MAY BE BEST TO STILL SHOW A HIGHER THAN
CLIMO POP-BUT LOWER THAN PREVIOUS DAYS. WILL ALSO SHOW RISING
AFTERNOON HIGHS. WEDNESDAY LOOKS SEASONABLE FOR THE MOST PART
ALTHOUGH SOME DEEP MOISTURE MAY BE LINGERING OVER FAR SOUTHERN
ZONES.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
AS OF 06Z...VFR THIS TAF VALID PERIOD...EXCEPT FOR A SHORT PERIOD
OF SUB-VFR VSBYS IN THE PRE-DAWN HOURS AT KFLO/KLBT. ONLY LIMITED
AMOUNTS OF LOW LEVEL MOISTURE ARE AVAILABLE FOR BR FORMATION. THE
BEST MOISTURE IS AT KFLO BUT A BROKEN LAYER OF MID CLOUDS SHOULD
PERSIST THROUGH SUNRISE. THUS BELIEVE THE CHANCE OF IFR IS LOW AT
KFLO AND LOW AT KLBT DUE TO LESS AVAILABLE MOISTURE.

MID LEVEL CLOUDS SCT DURING THE MORNING BUT COULD PERSIST INTO THE
AFTERNOON AT KLBT. SCT LOW/MID CLOUDS WITH THIN BKN HIGH CLOUDS
EXPECTED FOR MOST OF THE DAY AT THE REMAINING TERMINALS. WINDS
WILL BECOME E-ESE WITH STRONGEST SPEEDS AT THE COASTAL TERMINALS.

AFTER SUNSET THERE WILL BE SCT MVFR LEVEL LOW CLOUDS ADVECTING
INTO THE COASTAL TERMINALS...THEN EVENTUALLY THE INLAND TERMINALS
LATE IN THE TAF VALID PERIOD. MVFR CIGS ARE NOT ANTICIPATED AT
THIS TIME.

EXTENDED OUTLOOK...INCREASING CHANCES FOR SHRA/TSRA AND PERIODS OF
MVFR CONDITIONS FRIDAY THROUGH MONDAY AS A FRONT STALLS OVER THE
EASTERN CAROLINAS.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
AS OF 1:30 PM THURSDAY...NO CHANGES TO THE FORECAST WITH THE
LATEST UPDATE. RELEVANT PORTION OF PREVIOUS DISCUSSION FOLLOWS:

EASTERLY WINDS ARE EXPECTED OVERNIGHT BETWEEN HIGH PRESSURE ACROSS
VIRGINIA AND A STALLED FRONT EXTENDING FROM THE FLORIDA GEORGIA
LINE TO THE GULF STREAM WATERS OFF THE SOUTH CAROLINA COAST. WIND
SPEEDS SHOULD AVERAGE 10-15 KNOTS WHICH IS HELPING SUSTAIN A 2-3
FOOT 5-SECOND WIND CHOP. WHEN COMBINED WITH A SMALL SOUTHEAST
9-SECOND SWELL...COMBINED SEAS SHOULD AVERAGE AROUND 3 FEET.
ALTHOUGH A RENEGADE SHOWER CANNOT BE COMPLETELY RULED OUT...THE
BETTER CHANCES FOR SHOWERS APPEAR TO ACROSS INTERIOR SOUTH
CAROLINA THIS EVENING.

SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 PM WEDNESDAY...BETTER CHANCE OF POPS ACROSS THE COASTAL
WATERS THIS PERIOD AS STALLED FRONT/COASTAL TROUGH WILL BE PUSHED
BACK TOWARDS THE COAST THURSDAY BEFORE MOVING ONSHORE DURING
FRIDAY. WINDS WILL REMAIN AT OR BELOW 10 KTS WITH WEAK GRADIENT ON
THURSDAY BUT INCREASE FRIDAY WITH COASTAL TROF MOVING ONSHORE.
WINDS MAINLY E TO SE ON THURSDAY VEERING TO THE S-SW BY FRIDAY.
WAVES WILL AVERAGE 2-3 FT SEAS THROUGH THE PERIOD.

LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 PM WEDNESDAY...LIGHT SE WINDS ON SATURDAY AS FRONTAL
BOUNDARY JUST INLAND FROM THE COAST MOVES FURTHER WEST. SEAS
AROUND 3 FT FOR THE MOST PART AS WIND WAVES QUITE LIGHT BUT WNA
SPECTRAL PLOTS SHOWING A SELY SWELL. HEADING INTO SUNDAY A MINOR
VEER TO THE S AS THE BOUNDARY MOVES FURTHER INLAND AND WEAKENS
ALLOWING WEST ATLANTIC HIGH PRESSURE TO BECOME MORE PREDOMINANT
WITH LOCAL WIND GENERATION. SEAS RELATIVELY UNCHANGED. AS THIS
TREND CONTINUES INTO MONDAY A SIMILAR ONE COMPASS POINT VEER TO SW
CAN BE EXPECTED. THERE MAY BE AN OUTSIDE CHANCE FOR SOME
ADDITIONAL SWELL ENERGY SHOULD THE ATLANTIC TROPICAL DISTURBANCE
STRENGTHEN BUT THIS SYSTEM HAS BEEN STRUGGLING TO DEVELOP AND ITS
FUTURE PATH AND STRENGTH STILL PRETTY UP IN THE AIR.
-- End Changed Discussion --

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...CRM
NEAR TERM...REK/TRA
SHORT TERM...MAC
LONG TERM...MBB
AVIATION...MRR
MARINE...REK/TRA/MBB/MAC