Area Forecast Discussion
Issued by NWS Wilmington, NC

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000
FXUS62 KILM 260829
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
329 AM EST MON JAN 26 2015

.SYNOPSIS...
LOW PRESSURE AND A COLD FRONT WILL CROSS THE AREA TODAY AND
CONGEAL INTO A POWERFUL NEW ENGLAND NOR`EASTER. HIGH PRESSURE WILL
MOVE INTO THE CAROLINAS BY THURSDAY FOLLOWED BY ANOTHER COLD FRONT
THURSDAY NIGHT INTO FRIDAY. HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST OVER THE WEEKEND.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM MONDAY...A CLIPPER LOW WAS CENTERED ACROSS WESTERN
VIRGINIA WITH ITS TRAILING COLD FRONT DRAPED ACROSS THE
APPALACHIANS. THIS SYSTEM WILL RACE ACROSS THE CAROLINAS AND
VIRGINIA THIS MORNING WITH THE CENTER REDEVELOPING OFF THE VIRGINIA
CAPES THIS AFTERNOON. THE CENTER WILL THEN INTENSIFY RAPIDLY AS IT
MOVES SLOWLY NNE. THE LONGWAVE UPPER TROUGH WILL REACH THE EASTERN
CAROLINAS TODAY...BUT AS THE SYSTEM INTENSIFIES AND BECOMES
NEGATIVELY TILTED...THIS TROUGH WILL LINGER ACROSS THE AREA THROUGH
THE PERIOD.

VIGOROUS MID-LEVEL SHORTWAVE TROUGHS WILL ROUND THE BASE OF THE MAIN
TROUGH...PROVIDING ENERGY AND LIFT WHILE BRINGING PROGRESSIVELY
CHILLIER AIR UPSTAIRS. TEMPS AT 500 MB WILL DROP TO AROUND MINUS 26
DEG C TODAY AND MINUS 28 DEG C TONIGHT. STEEP LAPSE RATES WILL
DEVELOP AS TEMPS IN THE LOW LEVELS RISE WELL INTO THE 50S TODAY.
THIS WILL CREATE AN UNSTABLE ENVIRONMENT AND HELP TO WRING OUT THE
LIMITED MOISTURE THIS FAR SOUTH. MID LEVEL LAPSE RATES APPROACH 7
DEG C/KM AND MIXED LAYER CAPE VALUES DO SHOW THE INSTABILITY
ALTHOUGH THEY ARE VERY MODEST...ON THE ORDER OF 100-200 J/KG...
HIGHEST ACROSS NE PORTIONS OF THE FORECAST AREA.

ALTHOUGH NO HEAVY RAIN IS EXPECTED...INSTABILITY SHOWERS SHOULD
INCREASE IN NUMBER WITH PERHAPS THE BEST COVERAGE ACROSS OUR
NORTHERN ZONES IN CLOSEST PROXIMITY TO THE SURFACE LOW. WILL SHOW
POPS UP TO HIGH CHANCE LOW-END LIKELY ALONG AND N OF LBT AND EYF.
POPS WILL TRAIL OFF AS YOU PROGRESS SOUTH WHERE COVERAGE SHOULD BE
MORE SPOTTY. A RUMBLE OF THUNDER IS NOT IMPOSSIBLE...BUT REMOTE AND
DID NOT INCLUDE MENTION AT THIS TIME. INVERTED-V SOUNDINGS INDICATE
SOME GUSTY WINDS ARE LIKELY WITH ANY OF THE MORE PERSISTENT SHOWERS.
AS LOW PRESSURE INTENSIFIES OFF THE MID-ATLANTIC COAST...ITS
DEVELOPING PRECIPITATION SHIELD SHOULD EXPAND. WRAP AROUND
PRECIPITATION COULD BACK BUILD/PERSIST INTO PORTIONS OF THE FORECAST
AREA. THE HIGHEST RISK FOR SHOWERS AFTER DARK WILL BE ACROSS THE
CAPE FEAR AREA AND BACK TOWARDS EYF. IN FACT...THERE IS A VERY SMALL
CHANCE THAT SNOW WILL MIX IN WITH ANY RESIDUAL RAIN SHOWERS AS FAR
SOUTH AS PENDER COUNTY TOWARD MORNING. NO ACCUMULATION OF SNOW IS
EXPECTED GIVEN GROUND TEMPS WILL BE WELL ABOVE FREEZING AND EVEN AIR
TEMPS WILL NOT BE ANY LOWER THAN THE MID 30S. TEMPS SHOULD DROP TO
NEAR FREEZING FURTHER SW AND ESPECIALLY W OF THE AFOREMENTIONED AREA
WHERE THICK CLOUDS SHOULD EXHIBIT A DECREASING TREND OVERNIGHT. A
TIGHTENING PRESSURE GRADIENT WILL KEEP WINDS UP LATER THIS AFTERNOON
AND FOR MUCH OF THE NIGHT...W TO NW AT 15 TO 20 MPH WITH GUSTS UP TO
25 TO 30 MPH.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM MONDAY...BLOCKBUSTER STORM CLOBBERING NEW ENGLAND ON
TUESDAY AND AS AS USUAL WHEN THIS IS THE CASE COLD AIR WILL READILY
INVADE MOST AREAS EAST OF THE APPALACHIANS. A SMALL LAYER OF LOW
LEVEL MOISTURE STARTS OUT THE DAY BUT WITH A GREAT DEPTH OF THE
COLUMN A DRY NWRLY FLOW THIS SHOULD MIX OUT FOR NEARLY FULL
SUNSHINE. EVEN SO, THE CAA WILL CAP HIGHS IN THE MID 40S, SOME 10
DEGREES BELOW CLIMO. OFT TIMES WITH SUCH A LARGE AND STRENGTHENING
STORM OVER THE NORTHEASTERN U.S. IT IS OFTEN RATHER BLUSTERY LOCALLY
BUT THIS DOES NOT APPEAR TO BE IN THE OFFERING THIS TIME AROUND. WE
SEEM TO FIND OURSELVES IN A RELATIVE MINIMUM IN THE LOW LEVEL WIND
FIELD BETWEEN THE JET ASSOC WITH THE ACTUAL STORM CENTER AND THE
MAIN AXIS OF COLD AIR ADVECTION WEST OF THE LOW LVL THERMAL TROUGH
OVER THE GULF STATES. THERE WILL BE JUST ENOUGH WINDS TUESDAY NIGHT
TO PREVENT RADIATIONAL COOLING. SO IN AN AIRMASS COLD ENOUGH TO
BRING LOWS CLOSE TO 20 WE SHOULD INSTEAD REMAIN IN THE UPPER
20S...PERHAPS LOW 30S FAR SRN ZONES. UPPER TROUGH AXIS WELL OFFSHORE
BY WEDNESDAY WHILE THE AXIS OF HIGHEST SURFACE PRESSURES BUILDS
RIGHT OVERHEAD. SO WHILE THERE MAY BE SOME MINOR RECOVERY IN THE
BOUNDARY LAYER TEMPERATURES THE SHALLOW NATURE OF THE MIXING
(2200FT?) WILL BRING CHILLY HIGHS NEARLY IDENTICAL TO THOSE OBSERVED
TUESDAY. FORECAST SOUNDINGS WEDNESDAY NIGHT MUCH MORE TYPICAL OF
RADIATIONAL COOLING WITH NEAR ISOTHERMAL LAYER POSSIBLY AS DEEP AS
9KFT. HOWEVER DUE TO THE AFOREMENTIONED RECOVERY IN TEMPERATURES
WEDNESDAY NIGHT LOWS WILL BE SIMILAR TO THOSE OF THE NIGHT BEFORE.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 AM MONDAY...SURFACE HIGH MOVES OVERHEAD EARLY THURSDAY AND
JUST OFFSHORE IN A WEAKENING STATE LATER IN THE DAY. ZONAL MID LEVEL
FLOW NORMAL QUITE DRY BUT SOME PVA INDUCED BY THE WESTERLIES
REACTING WITH SOME LOW LEVEL MOISTURE FLOW IN THE SW WINDS TO BRING
AN INCREASE IN CLOUDS. MEANWHILE AFTERNOON TEMPS REBOUND CLOSE TO
CLIMO. WILL THIS MOISTURE BE ADEQUATE TO SUPPORT SOME PRECIPITATION
AS THE NEXT UPPER WAVE AND COLD FRONT PASS THROUGH THURSDAY NIGHT
INTO FRIDAY MORNING? HARD TO SAY THIS FAR OUT BUT GIVEN THE FAIRLY
ROBUST STRENGTH OF THE TROUGH THE SLIGHT CHANCE INHERITED POPS LOOK
FINE. EITHER WAY IT WILL STAY MILD ENOUGH TO PRECLUDE ANY PTYPE
CONCERNS. THE WEEKEND WILL BASICALLY JUST FEATURE COLD AIR ADVECTION
IN NORTHWESTERLY FLOW AROUND HUDSON BAY VORTEX. THERE MAY AT SOME
TIME BE ENOUGH OF A SPOKE OF ENERGY WITHIN THIS FLOW TO YIELD ASCENT
AND EVEN OFFSHORE PRESSURE FALLS. ANY SUCH DISTURBANCE IS FAR BEYOND
BEING SAMPLED BY UPPER AIR NETWORK AND SO SOLUTIONS MAY SHOW HIGH
VARIABILITY FROM RUN TO RUN. AT THIS TIME IT SEEMS MOST PRUDENT TO
FOCUS ON THE CHILLY TEMPS AND ADDRESS ANY CLOUD COVER AND LOW RAIN
CHANCES AT A FUTURE TIME.


&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 06Z...EXPECT VFR TO PREVAIL THROUGH THE VALID PERIOD...WITH
CLOUDS INCREASING OVERNIGHT AND SHOWERS POSSIBLE ON MONDAY AS A
QUICKLY PROPAGATING SYSTEM MOVES THROUGH THE AREA.

WHILE ONE MODEL SUGGESTS MARGINAL MVFR FOG DEVELOPMENT AT THE INLAND
SITES...AM EXPECTING INCREASED BOUNDARY LAYER WINDS TO KEEP
DEVELOPMENT CHANCES LOW. THROUGH THE OVERNIGHT HOURS WILL SEE A
GRADUAL INCREASE OF MID TO HIGH LEVEL CLOUDS AHEAD OF THE NEXT
SYSTEM...WITH VARIABLE WINDS AROUND 5 KT. AFTER DAYBREAK...WINDS
THROUGHOUT THE DAY WILL VEER...BECOMING WESTERLY WITH SUSTAINED
WINDS AOB 10 KT BY MORNING AND THEN INCREASING EVEN MORE TO AOB 12
KT WITH GUSTS AROUND 20 KT INTO THE EARLY AFTERNOON HOURS.
ISOLATED TO SCATTERED SHOWERS ARE POSSIBLE...THUS HAVE INTRODUCED
VCSH ATTM. LOW CLOUDS MOVE IN AS WELL...AND COULD NOT RULE OUT A
BRIEF PERIOD OF MVFR DUE TO LOW CIGS IN THE AFTERNOON...BUT
CONFIDENCE IS LOW ATTM. INTO THE LATE EVENING HOURS CHANCES OF
PRECIPITATION WILL DIMINISH...AND WINDS WILL BECOME NORTHWEST...
WITH GUSTS UP TO AROUND 20 KT CONTINUING.

EXTENDED OUTLOOK...SLIGHT CHANCE OF -RA/MVFR CIGS MONDAY. VFR
WEDNESDAY THROUGH FRIDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM MONDAY...A SMALL CRAFT ADVISORY IS IN EFFECT BEGINNING
LATE MORNING ACROSS THE SOUTHERN WATERS AND EARLY AFTERNOON NORTHERN
WATERS. THE SMALL CRAFT ADVISORY WILL CONTINUE INTO TUE MORNING. A
TIGHTENING PRESSURE GRADIENT WILL BRING SUSTAINED WINDS UP TO 20 TO
30 KT WITH GUSTS NEAR 35 KT FOR A TIME. WINDS WILL BE STRONGEST
TONIGHT AS LOW PRESSURE RAPIDLY INTENSIFIES OFF THE MID-ATLANTIC
COAST. THE DIRECTION WILL BE WSW THIS MORNING AND THEN W THIS
AFTERNOON AND EVE...VEERING TO NW OVERNIGHT. ALTHOUGH THE WIND
DIRECTION THIS PERIOD IS NOT ESPECIALLY CONDUCIVE FOR BUILDING
SEAS...SEAS WILL STILL MANAGE TO REACH 6 FT OR HIGHER ACROSS
PORTIONS OF THE OUTER WATERS AND UP TO 8 OR 9 FT AROUND FRYING PAN
SHOALS. DEVELOPING BACKSWELL MAY ALLOW THESE HIGHER SEAS TO PERSIST
ACROSS THE NORTHERN WATERS WELL INTO TUE.


SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 AM MONDAY...MODERATE OFFSHORE FLOW ON TUESDAY AS LOW
PRESSURE BOMB OFF THE NEW ENGLAND COAST BRINGS CYCLONIC FLOW ACROSS
THE ENTIRE EAST COAST. DUE TO THE DISTANCE OF THIS STORM AND THE
FACT THAT ITS BACKSWELL DOES NOT SIGNIFICANTLY REFRACT AROUND CAPE
HATTERAS TOWARDS OUR REGION IT SEEMS THAT WE MAY NOT SEE ANY
ADVISORIES SAVE FOR PERHAPS THE FIRST FEW HOURS OF THE PERIOD.
THEREAFTER DECREASING WINDS AND SEAS EXPECTED AS THE GRADIENT EASES.
NOT TOO FAR OFFSHORE HOWEVER THERE WILL STILL BE A BROAD AGITATED
WIND FIELD AND  MARINERS VENTURING OUT PAST OUR 20NM ZONES ARE URGED
TO CHECK WITH THE OFFSHORE WATERS FORECAST FROM OPC. A FURTHER
ABATING OF THE WIND FIELD IS SLATED FOR WEDNESDAY AND THE WIND
DIRECTION WILL ALSO BE VEERING AS HIGH PRESSURE BUILDS IN FROM THE
NORTHWEST...TAKING UP RESIDENCE ALONG THE COASTLINE BY
AFTERNOON/EVENING.


LONG TERM /THURSDAY THROUGH FRIDAY/...
AS OF 3 AM MONDAY...AN INITIALLY LIGHT SOUTH TO SOUTHWESTERLY RETURN
FLOW WILL BECOME ESTABLISHED ACROSS THE SOUTHEAST AS A WEAKENING
HIGH PRESSURE CELL MOVES OFF THE COAST. BY EVENING THIS WIND FIELD
WILL INCREASE A BIT IN RESPONSE TO AN APPROACHING COLD FRONT FROM
THE NORTHWEST. THE APPROACH AND PASSAGE OF THIS BOUNDARY WILL BRING
AN EXTENDED PERIOD OF VEERING DIRECTION WHICH PAIRED WITH THE HIGHER
WIND SPEEDS COULD LEAD TO SOME MARGINAL 6 FT SEAS OVER MAINLY
NORTHERN ZONES. NW WINDS BEHIND THE FRONT ON FRIDAY WITH WIND AND
SEAS BOTH SHOWING A DOWNWARD/IMPROVING TREND.



&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM THIS MORNING TO 7 AM EST
     TUESDAY FOR AMZ254-256.

     SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 7 AM EST
     TUESDAY FOR AMZ250-252.

&&

$$
SYNOPSIS...MBB
NEAR TERM...RJD
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...RJD/SGL
MARINE...





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