FXUS62 KILM 300912
AFDILM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
411 AM EST MON NOV 30 2009
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA THIS AFTERNOON AND EVENING.
HIGH PRESSURE WILL BRIEFLY BUILD OVER THE AREA TUESDAY AND LINGER
INTO TUESDAY NIGHT. LOW PRESSURE EMERGING FROM THE GULF OF MEXICO
COULD BRING SIGNIFICANT RAINFALL TO THE EASTERN CAROLINAS WEDNESDAY
AND WEDNESDAY NIGHT. BUILDING HIGH PRESSURE IS EXPECTED TO OFFER UP
COOLER BUT DRIER WEATHER ACROSS THE REGION LATE IN THE WEEK HEADING
INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM MONDAY...COLD FRONT SWIFTLY APPROACHING FROM THE
NORTHWEST WILL BRING SCATTERED SHOWERS TO THE FORECAST AREA STARTING
THIS AFTERNOON. PRECIP WILL PRECEDE FRONT...WHICH WILL MOVE ACROSS
THE EASTERN CAROLINAS THIS EVENING AND OFFSHORE BY MIDNIGHT. MODEL
CROSS SECTIONS SHOW BEST MOISTURE WILL BE OVER OUR NC COUNTIES.
OVERALL MOISTURE DEPTH AND TOTALS NOT THAT IMPRESSIVE...PW VALUES
PEAK AT ABOUT ONE AND A QUARTER INCHES THIS EVENING.
HOWEVER...DYNAMICS OF EVENT ARE IMPRESSIVE ENOUGH THAT WE SHOULD
HAVE EFFICIENT WRINGING OUT OF AVAILABLE MOISTURE AND THIS WILL BE
GOOD ENOUGH FOR AT LEAST SCATTERED SHOWERS. MAX TEMPS WILL REMAIN
ABOVE NORMAL TODAY AS MODERATE SWLY FLOW WILL CONTINUE INTO THE
AFTERNOON IN ADVANCE OF FROPA. LOOK FOR MAX TEMPS A DEGREE OR TWO
EITHER SIDE OF 70. MIN TEMPS A BIT MORE TRICKY. STRONG COLD SURGE
WILL KICK IN AFTER MIDNIGHT SO DEPENDING UPON TIMING OF SURGE EXPECT
LOWS IN A MORE SEASONAL RANGE...UPPER 30S INLAND TO LOWER 40S NEAR
THE COAST.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
EXPECT FAIR WEATHER ON TUESDAY WITH HIGHS AROUND 60 AS HIGH PRESSURE
CONTROLS AREA WEATHER. INCREASING CLOUDS ARE EXPECTED TUESDAY NIGHT
AS SW FLOW ALOFT RIDES OVER HIGH PRESSURE AT THE SURFACE. RAIN IS
POSSIBLE AFTER ABOUT 06Z. THERE IS SOME DISAGREEMENT BETWEEN THE
NAM AND GFS REGARDING THE TRACK OF THE LOW WEDNESDAY. THE NAM TAKES
THE LOW NORTHWARD THROUGH WESTERN TENNESSEE TOWARD CENTRAL OHIO
WHILE THE GFS RUNS THE LOW UP THE SPINE OF THE APPALACHIANS INTO
WEST-CENTRAL PA. THIS DIFFERENCE COULD HAVE SIGNIFICANT IMPACTS ON
THE WEATHER WEDNESDAY AND WEDNESDAY NIGHT.
THE MORE EASTWARD TRACK AND DEEPER CENTRAL PRESSURE OF THE GFS WOULD
LIKELY RESULT IN AN INITIAL ONSET OF RAIN WITH A TRANSITION TOWARD
CONVECTION AND A SEVERE WEATHER EVENT IN THE LATE AFTERNOON AND
NIGHT WEDNESDAY. THE MODEL FORECASTS A LOW LEVEL JET IN EXCESS OF
60 KT WITH OUR AREA IN THE WARM SECTOR. SHOULD THE LOW TRACK
FARTHER WEST AS IN THE NAM...ITS POSSIBLE THAT WE COULD REMAIN IN
THE COOL SECTOR AS AN IN-SITU DAMMING EVENT SETS UP WITH CONFLUENT
FLOW AT H5 OVER THE NE U.S. AT PRECIPITATION ONSET. IF THERE WERE
SEVERE WEATHER IN THIS CASE...IT WOULD LIKELY BE ALONG A COASTAL
FRONT WITH LITTLE INLAND PENETRATION.
THE PRESENT FORECAST FOR WEDNESDAY AND WEDNESDAY NIGHT MORE CLOSELY
RESEMBLES THE GFS WITH A RAIN EVENT TRANSITIONING TO THE CONVECTIVE
MODE BY WEDNESDAY NIGHT. AT THIS TIME...THE FORECAST DOES NOT
REFLECT SEVERE WEATHER POTENTIAL DUE TO THE MODEL CONFLICT.
TEMPERATURES WEDNESDAY ARE PROBLEMATIC AT BEST AS WE COULD SEE MOST
OF THE AREA STUCK IN THE 50S WITH RAIN WEDNESDAY AND WEDNESDAY NIGHT
OR TEMPERATURES COULD REBOUND WELL INTO THE 60S OR LOWER 70S IF WE
GET INTO THE WARM SECTOR. AT PRESENT...THE FORECAST GOES FOR UPPER
50S INLAND TO MID 60S COASTAL AREAS WEDNESDAY WITH MINS WEDNESDAY
NIGHT WITHIN ABOUT 5 DEGREES OF WEDNESDAYS HIGHS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
AFTER SOME RESIDUAL CLOUDS AND PERHAPS A FEW SHOWERS THE FIRST HALF
OF THURSDAY...A COLD FRONT WILL SWEEP THROUGH THE AREA AND HIGH
PRESSURE WILL BUILD INTO THE AREA IN ITS WAKE. THE RESULT WILL BE
FAIR BUT COOL WEATHER THROUGH SUNDAY.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 06Z...HIGH PRESSURE OFFSHORE KEEPING VFR CONDITIONS AT ALL THE
TERMINALS TONIGHT WITH LIGHT S/SW WINDS. HIGH LEVEL CI WILL AGAIN
FILTER IN ALOFT ASSOCIATED WITH A COLD FRONT THAT WILL APPROACH THE
AREA TOMORROW NIGHT AND WILL BRING SOME LIGHT SHOWERS TO THE
TERMINALS TOMORROW NIGHT.
CIRRUS SLOWLY BEGINNING TO INCREASE IN COVERAGE AND WILL BECOME BKN
TO OVC BY TMRW AFTN. A COLD FRONT APPROACHING FROM THE WEST WILL
BEGIN TO LOWER CIGS BY LATE TMRW. TIMING THE FROPA IS BIGGEST
CHALLENGE THIS FORECAST PERIOD...BUT EXPECT SOME VERY LIGHT SHOWERS
TO OCCUR AT LBT/FLO BY 00Z WEDNESDAY...WITH THE COASTAL TERMINALS
RECEIVING SOME LIGHT RAIN JUST AFTER 00Z. ANY RAIN THAT FALLS WILL
BE LIGHT AND SHOULD NOT REDUCE VSBYS BELOW VFR...BUT SOME MVFR CIGS
ARE POSSIBLE ESPECIALLY AT ILM/CRE/MYR. ONLY OTHER CONCERN TOMORROW
WILL BE GUSTY W/SW WINDS AHEAD OF THE FROPA. WITH TIGHTENED GRADIENT
NEAR THE FRONT...AND ANOTHER DAY OF DEEP MIXING...EXPECT 20 KT GUSTS
AT ALL THE TERMINALS SHORTLY AFTER SUNRISE. WINDS WILL DECREASE
TOMORROW NIGHT ONCE MIXING SUBSIDES...BUT WILL REMAIN AROUND 10 KT
AS FRONT APPROACHES.
WAS A LITTLE MORE CONCERNED ABOUT FOG TONIGHT SINCE THE SOUTHERLY
FLOW HAS INCREASED LOW LEVEL MOISTURE AT THE TERMINALS TODAY.
HOWEVER...WINDS LOOK TO STAY JUST HIGH ENOUGH TO KEEP ANY FOG MIXED
OUT THROUGH THE NIGHT. CANNOT RULE OUT SOME LIGHT GROUND FOG AT THE
USUAL TERMINALS...CRE/LBT/FLO...BUT HAVE NOT PUT ANYTHING IN THE
TAFS SINCE CHANCE OF REDUCED VSBYS DUE TO FOG IS VERY LOW.
EXTENDED OUTLOOK...IFR POSSIBLE WITH A LOW PRESSURE SYSTEM WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 AM MONDAY...RAISING SMALL CRAFT ADVISORY FOR ALL WATERS FOR
THIS EVENING AND OVERNIGHT AS A STRONG COLD SURGE FOLLOWING COLD
FROPA BRINGS STRONG AND GUSTY NW TO NORTHERLY WINDS TO THE FORECAST
AREA. EXPECT WINDS AND WIND GUSTS IN THE 25 KT RANGE. AS FLOW WILL
BE OFFSHORE HIGHEST SEAS WILL BE FOUND 20 NM OUT AND WILL BE IN THE
6 FT RANGE. EXPECT FRONT TO MOVE OFFSHORE BY AROUND MIDNIGHT.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
TUESDAY WILL BEGIN WITH N TO NW WINDS AT OR JUST BELOW SCA CRITERIA.
WINDS WILL DIMINISH TUESDAY AND TUESDAY NIGHT AS THEY BECOME N TO NE
AT 15 KT OR LESS BY EVENING. SEAS WILL FALL TO 2 TO 3 FEET BY
TUESDAY NIGHT. THE IMPROVED CONDITIONS WILL BE SHORT LIVED THOUGH AS
WINDS VEER THROUGH EAST TO S TO SW WEDNESDAY AND WEDNESDAY NIGHT.
SPEEDS WILL RAMP UP TO 25 TO 30 KT AND SEAS COULD BUILD AS HIGH AS 8
TO 10 FEET AT 20 NM.
LONG TERM /THURSDAY THROUGH FRIDAY/...
WINDS WILL SHIFT TO THE W THURSDAY MORNING THEN NW THURSDAY
AFTERNOON AND DECREASE TO AROUND 15 KT. WINDS WILL TURN MORE
NORTHERLY BY FRIDAY AT 10 TO 15 KT. SEAS WILL SUBSIDE THROUGH THE
PERIOD...REACHING 2 TO 3 FEET BY FRIDAY.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST
TUESDAY FOR AMZ250-252-254-256.
&&
$$
NEAR TERM...REK
SHORT TERM..31
LONG TERM...31
AVIATION...REK/JW
