000
FXUS62 KILM 100528
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
1228 AM EST WED MAR 10 2010

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH EARLY
WEDNESDAY. A SLOW MOVING STORM SYSTEM APPROACHING FROM THE CENTRAL
UNITED STATES WILL AFFECT THE AREA FROM LATE WEDNESDAY INTO THE
UPCOMING WEEKEND. ACCOMPANYING THE STORM SYSTEM WILL BE INCREASING
CHANCES FOR RAIN WEDNESDAY NIGHT THROUGH FRIDAY. DRY WEATHER IS
EXPECTED TO RETURN FOR THE LATTER HALF OF THE WEEKEND INTO EARLY
NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 900 PM TUESDAY...SOMEWHAT FLATTENED UPPER RIDGE TO AFFECT THE
AREA OVERNIGHT...WITH THE RIDGE AXIS PROGGED TO MOVE EAST TO JUST
OFF THE SE U.S. COAST BY DAYBREAK WEDNESDAY. THE 1ST UPPER CLOSED
LOW AND ITS ACCOMPANYING SFC LOW MOVE NNE WITHIN THE PLAINS STATES
OVERNIGHT. THE ATM COLUMN IS PROGGED TO MOISTEN UP SOME...ESPECIALLY
SW PORTIONS OF THE ILM CWA WITH GULF MOISTURE BECOMING MORE
AVAILABLE...AS WELL AS LOW LEVEL SOUTHERLY RETURN FLOW AROUND THE
SFC HIGH. DECENT SWATH OF UVVS TO DEVELOP AND/OR REACH THE SW
PORTIONS BY DAYBREAK WED IN RESPONSE TO THE FORECAST AREA WITHIN THE
LEFT FRONT QUADRANT OF A 300 MB JET LOCATED FROM SOUTHERN TEXAS TO
FLORIDA. ENOUGH MOISTURE WILL RESIDE IN THE ATM TO BE CONDUCIVE FOR
PCPN DEVELOPMENT BY DAYBREAK WEDNESDAY ESPECIALLY ACROSS THE SW
PORTIONS...AND SPREADING NEWARD DURING THE DAY. AS FOR PCPN
AMOUNTS...ONLY TALKING LESS THAN ONE TENTH OF AN INCH INTO WED
EVENING. WILL LIKELY HAVE TO INCREASE OVERNIGHT POPS AND CLOUD
COVER...AS WELL AS MIN TEMPS. INSULATING EFFECTS FROM THE CLOUDS AND
POSSIBLE LATE NIGHT PCPN WILL KEEP MIN TEMPS UP...RATHER THEN ANY
WAA. AFTN/EVENG SEA BREEZE HAS PUSHED DEWPOINTS UPWARDS AND DONT
EXPECT THEM TO RECOVER WITH THE OVERALL SYNOPTIC PATTERN OF
INCREASING DEWPOINTS TO OCCUR OVERNIGHT INTO WEDNESDAY.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...FORECAST AREA WILL REMAIN BETWEEN HIGH PRESSURE
OFF THE EAST COAST AND LARGE STORM SYSTEM OVER THE MIDWEST. DEEP
SOUTH TO SOUTHWEST FLOW WILL ADVECT GULF AND ATLANTIC MOISTURE INTO
THE SOUTHEASTERN US. INCREASING MID LEVEL MOISTURE WED RESULTS IN
ABUNDANT CLOUD COVER...BUT DRY LOW LEVELS AND LIMITED INSTABILITY
WILL KEEP POPS LOW. WEAK WARM ADVECTION WILL PUSH HIGHS INTO THE
UPPER 60S/LOWER 70S DESPITE CLOUD COVER. PRECIP CHANCES INCREASE WED
NIGHT AS LOWER LEVELS BECOME SATURATED AND FLOW ALOFT BECOMES
DIVERGENT. CLOUDS AND SOUTHERLY FLOW WILL KEEP LOWS 50S. HIGHEST
POPS THU AS PASSING SHORTWAVE ENHANCES LIMITED SURFACE BASED
INSTABILITY. THOUGH CAPE IS LOW CANNOT RULE OUT A FEW THUNDERSTORMS.
WARM ADVECTION CONTINUES ON THU BUT PRECIP AND INCREASED CLOUD COVER
WILL KEEP HIGHS A LITTLE CLOSER TO CLIMO. LINGERING CLOUDS THU NIGHT
KEEP LOWS IN THE LOW TO MID 50S. MAY HAVE SOME LIGHT SHOWERS THU
NIGHT BUT DRY AIR ALOFT AND MID LEVEL STABILITY WILL KEEP COVERAGE
MINIMAL.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...BY FIRST LIGHT OF FRIDAY A SLUGGISHLY MOVING
UPPER LOW WILL BE POSITIONED OVER THE MIDDLE MISSISSIPPI VALLEY
WITH DEEP SOUTHERLY FLOW ALREADY ENTRENCHED ACROSS THE EASTERN
CAROLINAS. SEVERAL IN A SERIES OF IMPULSES ALOFT WILL TRACK FROM
SOUTHWEST TO NORTHEAST AHEAD OF THIS LARGE SCALE CYCLONE IN THE
PERIOD FRIDAY THROUGH SUNDAY...PRODUCING PERIODS OF SHOWERS. QPF
WISE THE BEST RAIN POTENTIAL ARRIVES FRIDAY NIGHT INTO EARLY
SATURDAY MORNING AS ONE OF THE STRONGER IMPULSE TRACKS OVERHEAD.
FOLLOWING THIS FEATURE COLUMN WIND FLOW WILL SHIFT TO THE WEST AS
BOTH THE UPPER LOW AND ITS ATTENDANT SURFACE LOW PULL NORTH OF THE
FORECAST AREA. THIS WILL SHARPLY DECREASE RAINFALL POTENTIAL...BUT
LIGHTER SHOWERS WILL LIKELY LINGER THROUGH SATURDAY AS THE
SOUTHERN EXTENT OF A COOL POOL ALOFT AND MARCH INSOLATION
INTERACT. WILL KEEP MENTION OF PCPN THROUGH SATURDAY EVENING AS
THE LAST STRONG LOBE OF VORTICITY PASSES OVER THE FORECAST AREA
ROUNDING THE BASE OF THE EXITING UPPER LOW.

EXPECT ABOVE NORMAL TEMPERATURES IN BLUSTERY SOUTHERLY FLOW FRIDAY
INTO EARLY SATURDAY...FOLLOWED BY NEAR NORMAL TEMPERATURES FOR MID
MARCH SUNDAY THROUGH TUESDAY AS COOLER AIR FILTERS INTO THE REGION.
BEYOND TUESDAY A BAG OF MIXED SIGNALS IN THE MODELS...TYPICAL OF A
SPRING TRANSITION...HINT THAT WINTER IS NOT COMPLETELY OVER WITH.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
INCREASING MID CLOUDS ARE EXPECTED OVER THE NEXT SIX HOURS AS
MOISTURE INCREASES STEADILY FROM THE WEST WELL IN ADVANCE OF A LARGE
LOW PRESSURE SYSTEM. LIGHT SOUTHWEST SURFACE WINDS ARE EXPECTED AND
WINDS WITHIN THE BOUNDARY LAYER WILL BE HIGH ENOUGH THAT NO FOG IS
EXPECTED. LOOK FOR SHOWERS POSSIBLE BY LATE AFTERNOON OR THIS
EVENING AS SOME WEAK ISENTROPIC LIFT BEGINS. CONDITIONS SHOULD
REMAIN VFR THROUGH 00Z...WITH A SLIGHT CHANCE OF MVFR CEILINGS IF
THE SHOWERS HAPPEN TO BECOME MODERATE.

EXTENDED OUTLOOK...MEDIUM CONFIDENCE FOR PERIODS OF IFR/RAIN AND
POSSIBLE THUNDERSTORMS AS APPROACHING STORM SYSTEM MOVES INTO THE
AREA FOR THURSDAY. CONDITIONS WILL BE UNSETTLED THROUGH  SATURDAY
MORNING WITH INTERMITTENT LOW CEILINGS AND PRECIP. LOW CONFIDENCE
FOR POSSIBLE SHOWERS FOR SUNDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 900 PM TUESDAY...PROGGED SFC PRESSURE PATTERN AND GRADIENT
CURRENTLY YIELDING S TO SW WINDS AROUND 10 KT. LATEST MODEL MOS
GUIDANCE CONTINUES THESE WINDS OVERNIGHT AND SEE NO REASON TO SWAY
FROM THIS OUTPUT. SEAS AROUND 2 FT WILL CONTINUE OVERNIGHT...MAINLY
IN AN ESE 10 SECOND PLUS GROUND SWELL. THE STRATIFORM TYPE LIGHT
PCPN WILL RESIDE OVER LAND AREAS.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...SOUTHERLY FLOW OVER THE WATERS WED STARTS TO
INCREASE DURING THE AFTERNOON AS GRADIENT BEGINS TIGHTENING. SPEEDS
WED AND WED NIGHT REMAIN UNDER 15 KT WITH SEAS UNDER 4 FT. SPEEDS
REALLY START TO PICK UP THU AS GRADIENT BECOMES PINCHED. FLOW
BECOMES A LITTLE MORE ONSHORE WITH SPEEDS NEAR 20 KT THU AFTERNOON.
INCREASED ONSHORE FLOW WILL BUILD SEAS THU...LIKELY REQUIRING A
HEADLINE IN THE AFTERNOON. STRONG ONSHORE FLOW CONTINUES OVERNIGHT
AHEAD OF WEAK WAVE CROSSING SOUTHERN SC.

LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 PM TUESDAY...THE OCEAN WILL BE ROUGHED UP FROM SE FETCH
AND SMALL CRAFT ADVISORY FLAGS WILL LIKELY BE RAISED AT DAYBREAK
FRIDAY...BUT SHOULD SUBSIDE BELOW 6 FEET BY FRIDAY AFTERNOON OR
EARLY EVENING WITH EASING SSE WINDS OFFSHORE. MODERATE WESTERLY
WIND FLOW MARKS THE REMAINDER OF THE FORECAST PERIOD WITH DEEP LOW
PRESSURE SITUATED NORTH OF THE WATERS...AND HIGH PRESSURE ANCHORED
OVER SOUTHERN FLORIDA AND THE BAHAMAS. A SMALL CRAFT ADVISORY FOR
STRONG WEST WINDS MAY BE NEEDED SATURDAY NIGHT AS LOW PRESSURE
DEEPENS NORTH OF THE AREA.

&&

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

&&

$$

SYNOPSIS...TRL
NEAR TERM...DCH
SHORT TERM...III
LONG TERM...MJC
AVIATION...TRA

NWS ILMNWS Office Area Forecast Discussion