575
FXUS62 KILM 161917
AFDILM
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
317 PM EDT WED OCT 16 2013
.SYNOPSIS...
CLOUDINESS WILL REMAIN AS A COLD FRONT APPROACHES FROM THE WEST
AND MOVES THROUGH THURSDAY NIGHT. SMALL RAIN CHANCES CROP UP
FRIDAY AND SATURDAY AS THE BOUNDARY STALLS NEAR THE COAST. SOME
SUNSHINE SHOULD RETURN TOWARDS THE BEGINNING OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
AS OF 300 PM WEDNESDAY...TODAY'S WEATHER OF MOSTLY CLOUDY SKIES WITH
A GRADUAL TREND OF BECOMING PARTLY CLOUDY IN SOME AREAS...AND TEMPS
IN THE LOW 70S DOESN'T STEER FAR FROM WHAT WE HAVE SEEN OVER THE
PAST SEVERAL DAYS. THINGS START TO SLIGHTLY CHANGE THROUGH EARLY
THURSDAY MORNING AS THE STAGNANT LOW PRESSURE CENTERED OFFSHORE IS
EXPECTED TO LIFT NEWARD...ALLOWING FOR THE LOW CLOUDS TO FINALLY
DISPERSE. HOWEVER...MOISTURE WILL CONTINUE TO STREAM SW TO NE ACROSS
THE SOUTHEAST US...JUST WEST OF OUR AREA...IN ASSOCIATION WITH AN
APPROACHING COLD FRONT...NESTLED IN BETWEEN THE WEAKENING UPPER
LEVEL RIDGE OVER OUR AREA AND A STRENGTHENING TROUGH OUT WEST. AS A
RESULT...MID TO HIGH LEVEL CLOUDS WILL BEGIN TO INFILTRATE INTO
MAINLY OUR WESTERN PORTIONS.
FOR OVERNIGHT...HAVE LOWERED TEMPS EVER SO SLIGHTLY...AS LACK OF LOW
CLOUD DECKS AND PREVAILING LIGHT AND VARIABLE WINDS COULD ALLOW FOR
SFC TEMPS TO COOL TO THE LOWER 60S...WITH POSSIBLE UPPER 50S INLAND.
CANNOT RULE OUT PATCHY AREAS OF FOG ALONG THE SC COAST...BUT OVERALL
THINK MID TO UPPER CLOUDS WILL LIKELY INHIBIT FAVORABLE RADIATIONAL
COOLING CONDITIONS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...THE TREND OF CLOUDY WEATHER CONTINUES ON
THURSDAY AS FAIRLY DEEP MOISTENING WILL BE UNDERWAY AHEAD OF A COLD
FRONT. FCST SOUNDINGS SHOW PW INCREASING TO 1.6-1.8 INCHES OR SO IN
DEEP LAYER WSW FLOW. DESPITE THE CLOUDINESS MANY PLACES SHOULD
MANAGE A HIGH OF 80 AWAY FROM ANY OCEAN INFLUENCE. THE BOUNDARY
PUSHES TROUGH MOSTLY RAIN-FREE LATE THURSDAY NIGHT WHILE
DECELERATING AS IT BECOMES INCREASINGLY ALIGNED WITH STEERING FLOW.
THE BOUNDARY WILL CONTINUE TO MAKE VERY SLOW PROGRESS OFFSHORE ON
FRIDAY...AT WHICH TIME SOME LARGE DIFFERENCE IN TEMPERATURE GUIDANCE
CROP UP. THE GFS FOR THE MOST PART SHOWS AN AFTERNOON AS WARM AS
THURSDAY FOR THE MOST PART WHILE THE WRF SHOWS MANY LOCATIONS
STRUGGLING OR EVEN FAILING TO TOP 70 FOR A HIGH. GIVEN THE VERY
SHALLOW NATURE OF THE COOL SURFACE AIRMASS FEEL THAT THE COOLER
NUMBERS ARE MORE ACCURATE...BUT POSSIBLY A LITTLE TOO COOL AS THERE
MAY BE A FEW BREAKS OF SUN. CURRENT FCST HOLDS PLACES IN THE MID
70S.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...BROAD MID LEVEL TROUGHING OVER MUCH OF THE
COUNTRY WILL MAINTAIN DEEP SOUTHWEST FLOW OVER THE SOUTHEAST...
KEEPING A SURFACE BOUNDARY STALLED IN THE AREA. DEEP MOISTURE
COMBINED WITH A SERIES OF WEAK SURFACE WAVES TRAVELING NORTHEAST
ALONG THE BOUNDARY WILL MAINTAIN CLOUD COVER AND THE THREAT OF LIGHT
PRECIP THROUGH SUN AFTERNOON. A SUBTLE SHIFT IN THE LOCATION OF THE
5H TROUGH AXIS ALONG WITH SURFACE HIGH MIGRATING EAST HELPS PUSH THE
STALLED BOUNDARY AND ITS ASSOCIATED MOISTURE OFFSHORE FOR MON AND
TUE. ANOTHER COLD FRONT APPROACHES FROM THE NORTHWEST TUE NIGHT INTO
WED. THE FRONT LACKS MOISTURE AND DYNAMICS WHICH...ALONG WITH ITS
EARLY MORNING ARRIVAL...WILL HELP KEEP POP LOW. GIVEN THE
UNFAVORABLE TIMING AND THE UNCERTAINTY FOR DAY 7 WILL INTRODUCE A
SLIGHT CHANCE OR SILENT POP FOR TUE NIGHT AND WED. THERE WILL BE AN
AIR MASS WITH TEMPS NEAR TO SLIGHTLY ABOVE CLIMO THROUGH TUE
DROPPING BELOW CLIMO FOR WED.
&&
.AVIATION /18Z WEDNESDAY THROUGH SUNDAY/...
AS OF 18Z...VISIBLE SATELLITE IMAGERY SHOWS LOW CLOUDS WILL PLAGUE
OUR CWA AGAIN THIS AFTERNOON. MVFR CIGS ARE BEING REPORTED AT MOST
SITES...WITH THE LOWEST CIGS ALONG THE COAST. KFLO/KLBT COULD SEE
VFR CONDITIONS DEVELOP LATER TODAY AS THE STRATOCU THINS OUT. NOT AS
OPTIMISTIC ABOUT THE LOW CLOUDS SCATTERING OUT ALONG THE COAST...AND
MVFR/VFR CIGS ARE EXPECTED INTO THE EVENING HOURS. THE WINDS WILL BE
LIGHT AND VARIABLE AROUND 5 KTS WITH WEAK HIGH PRESSURE ALONG THE
EAST COAST. CALM WINDS AND MOIST LOW-LEVELS OVERNIGHT COULD SUPPORT
FOG FORMATION AFTER 06Z THURSDAY. HOWEVER...INCREASING MID TO HIGH
CLOUDS AHEAD OF A COLD FRONT WILL INHIBIT DENSE FOG FORMATION.
THEREFORE...WILL ONLY MENTION MVFR VSBYS ATTM. EXPECT MAINLY VFR ON
THURSDAY WITH SOUTHWEST WINDS AOB 10 KTS.
EXTENDED OUTLOOK...SLIGHT CHANCE OF SHOWERS LATE THURSDAY INTO EARLY
FRIDAY WITH A COLD FRONT. ADDITIONAL SHOWERS ARE POSSIBLE OVER THE
WEEKEND AS THE FRONT STALLS NEAR OUR AREA.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM WEDNESDAY...AS LOW PRESSURE CENTERED OFFSHORE GRADUALLY
BEGINS ITS PROGRESSION TO THE NORTHEAST...10 KT WINDS WILL GRADUALLY
DECREASE TO VARIABLE 5 KT WINDS OVERNIGHT AS THE PRESSURE GRADIENT
RELAXES OVER THE AREA. SEAS 4 TO 5 FT TODAY WILL CONTINUE ON A
GRADUAL DOWNWARD TREND AS THE AREA LOSES ITS AFFECTS FROM PREVIOUS
BACK SWELL AND WEAK HIGH PRESSURE SETS UP SOUTHWEST OF THE AREA. AS A
RESULT...SEAS WILL BECOME 1 TO 3 FT OVERNIGHT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...SOUTHWESTERLY PREFRONTAL WINDS ON THURSDAY TO
PICK UP A FEW KNOTS AS THE DAY WEARS ON...EVEN INCREASINGS CWF WINDS
A CATEGORY THURSDAY NIGHT. THIS WILL BE RELATIVELY SHORT-LIVED
HOWEVER AS COLD FRONT PUSHES THROUGH LATE BRINGING A VEER AND A
DECREASE IN WIND SPEED. AS SUCH NOT EXPECTING ANY FLAGS/HEADLINES AS
SEAS LIKELY DONT BUILD TO MORE THAN 4 FT ALONG OUTER PORTIONS OF AMZ
250 AND 252. THE BOUNDARY WILL BE SLOWING IN FORWARD SPEED. THIS HAS
CAST SOME UNCERTAINTY AS TO HOW FAR OFF TO THE SOUTH AND EAST IT
WILL BE MOST OF FRIDAY. CURRENTLY PREFERRING A SOLUTION FARTHER TO
THE SOUTH WHICH WILL KEEP A NORTHERLY FLOW LOCALLY...BUT SOME
GUIDANCE HINTS AT A MUCH CLOSER BOUNDARY AND LIGHTER AND VARIABLE
WINDS.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 3 PM WEDNESDAY...WINDS UNDER 10 KT WILL CONTINUE FOR MUCH OF
THE PERIOD AS STALLED SURFACE BOUNDARY LINGERS OVER THE WATERS. WEAK
GRADIENT WILL KEEP DIRECTION VARIABLE...BUT WINDS WILL GENERALLY
HAVE A WEST OR A NORTHWEST COMPONENT. FRONT SHIFTS FARTHER OFFSHORE
SUN NIGHT INTO MON AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST.
GRADIENT TIGHTENS UP A LITTLE BIT WITH SPEEDS INCREASING TO 10 TO 15
KT AND BECOMING NORTH TO NORTHEAST. SEAS WILL BE AROUND 2 FT THROUGH
THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY FROM 7 PM TO 10 PM EDT THIS EVENING FOR
NCZ107.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...SGL
SHORT TERM...MBB
LONG TERM...III
AVIATION...BJR