Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 170824
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
424 AM EDT FRI OCT 17 2014

.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE GREAT LAKES TODAY AND THROUGH THE
FORECAST AREA EARLY SATURDAY. HIGH PRESSURE THEN BRIEFLY BUILDS INTO
THE REGION LATE SUNDAY INTO MONDAY. ANOTHER COLD FRONT SHOULD ARRIVE
LATE MONDAY INTO TUESDAY. A SECONDARY LOW PRESSURE SYSTEM IS
PREDICTED TO DEVELOP JUST EAST OF THE FORECAST AREA ALONG THE
FRONT LATER TUESDAY. THIS LOW SHOULD MOVE NORTHEAST VERY SLOWLY
REACHING CAPE COD ON THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THERE WILL BE SOME AREAS OF FOG EARLY THIS MORNING. THE AREAS OF BKN
MID LEVEL CLOUDS WILL LIKELY KEEP THE FOG FROM BECOMING TOO
WIDESPREAD OR TOO THICK. NO FLAGS ARE ANTICIPATED...BUT A SPS MAY BE
ISSUED IF NEEDED.

WEAK RIDGING WILL BE ACROSS THE AREA TODAY AS THE UPPER LOW/TROUGH
HAS MOVES NE OF THE AREA. SKY COVER WILL RANGE FROM MOSTLY CLR
ACROSS THE SRN/ERN AREAS TO PARTLY SUNNY NORTH/WEST. TEMPERATURES
TODAY WILL REMAIN A BIT ON THE MILD SIDE WITH HIGHS IN THE UPPER
60S/LOW 70S EXPECTED. WINDS WILL BE WRLY THIS MORNING...THEN BECOME
SW THIS AFTERNOON. OVERALL...A PLEASANT DAY EXPECTED.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
A COLD FRONT WILL APPROACH THE AREA TONIGHT. A SRLY FLOW WILL
DEVELOP THIS EVENING AND REMAIN IN PLACE OVERNIGHT. THIS WILL KEEP
MILD TEMPS ACROSS THE AREA...SO LOWS TONIGHT WILL BE IN THE LOW/MID
50S IN MOST AREAS...SOME UPPER 40S ACROSS THE FAR NORTH. THERE WILL
BE ADDITIONAL CLOUDS OVERNIGHT...BUT NO PCPN IS EXPECTED WITH THE
APPROACHING FRONT.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
THE LONG TERM CONTINUES TO SHOW A PAIR OF DEEP SYSTEMS AFFECTING OUR
CWA WITH THE LATTER ONE LIKELY TO CUT OFF AND ONLY SLOWLY MEANDER TO
THE EAST IN THE MIDDLE OF NEXT WEEK. WHILE THE IMPACT/DETAILS REMAIN
UNCERTAIN, TEMPERATURE-WISE WE ARE CONFIDENT THIS WILL BE A FAR
CRY FROM THE CURRENT SPELL OF UNSEASONABLY WARM WEATHER WE ARE
EXPERIENCING.

THE INITIALIZATION OF THE CLOSED LOW OVER MN LOOKED SLIGHTLY TOO
ROBUST. THE DIGGING SHORT WAVE PASSING THROUGH ON SATURDAY NIGHT
LOOKS WELL INITIALIZED IN WESTERN CANADA, WHILE THE PIECE OF ENERGY
THAT WILL BECOME OUR MIDWEEK CLOSING LOW IS STILL IN THE EASTERN
PACIFIC. THAT LOOKS TO BE WELL SAMPLED STARTING WITH THE 12Z RUN
ON SATURDAY. THE RIDGING ON BOTH SIDES OF THAT CLOSING LOW HAVE
TAKEN TURNS IN HAVING THE HONORS OF FORCING THE PROCESS. THE ECMWF
AND GEFS ENSEMBLE MEANS WHILE SUPPORTIVE OF THEIR OPS HAVE MOST OF
THEIR "NOISE" NORTH OF THE SYSTEM SUGGESTING THE MORE NORTHERN
2NDRY CYCLOGEN SOLUTIONS HAVE HIGHER PROBABILITY. LATEST WPC GUIDANCE
AND TO THE CLOSEST EXTENT THE OP CAN GGEM LEANS THIS WAY. WE ARE
STILL 4 TO 6 DAYS AWAY AND WAY TOO SOON TO BE CONFIDENT ABOUT ANY
ONE SOLUTION/EVOLUTION.

ON SATURDAY WE ARE EXPECTING THE CDFNT TO PASS EARLY, BUT ADDITIONAL
SHORT WAVES WILL BE PASSING THROUGH THE DAY. WITH THE SOUNDING CAP
AT A FAIRLY HIGH LEVEL (AROUND 10K) AND DESTABILIZATION OCCURRING
BELOW IT, WE KEPT THE LOW CHANCE OF SHOWERS IN THE NORTHWEST PART
OF OUR CWA WHERE DEEPER MOISTURE AND ELEVATION MAY BE THE KEY TO
GET PRECIPITATION TO REACH THE GROUND. MODELING CAA IS SLIGHTLY
FASTER AND WE EDGED MAX TEMPS DOWN EVER SO SLIGHTLY. IT WILL ALSO
BE RATHER BREEZY EVEN IF MAX TEMPERATURES HAVE ONE MORE DAY OF
BEING MILDER THAN NORMAL.

WHILE THE SHORT WAVES ASSOCIATED WITH THE MN CLOSED LOW MOVE THROUGH
ON SATURDAY, ANOTHER STRONG SHORT WAVE EMANATING FROM WESTERN CANADA
IS GOING TO SHARPEN THE TROF ONCE AGAIN ON SATURDAY NIGHT. THIS
SHORT WAVE IS PREDICTED TO REMOVE THE CAP AND POTENTIALLY GIVE A
CHANCE/SLIGHT CHANCE OF SHOWERS/SPRINKLES THRUT OUR CWA. THERE ARE
DIFFERENCES AS TO WHETHER THE SOUTHERN PIECE OF ENERGY PASSES THRU
OR SOUTH OF OUR CWA. THERE IS BETTER CONSENSUS ABOUT THE NORTHERN
SHORT WAVE. CLOSER TO THE SURFACE, THE NORTHWEST FLOW OFF OF LAKE
ONTARIO SHOULD PRODUCE SHOWERS REGARDLESS OF SAID FEATURE. BUT,
WITH BOTH FORCING MECHANISMS ACTING IN CONCERT FOR A LITTLE WHILE,
WE INCLUDED A LOW CHANCE OF SHOWERS NORTH. BY LATE SATURDAY NIGHT
IF SHOWERS CAN STILL MAKE IT INTO OUR CWA IT COULD BE COLD ENOUGH
FOR SOME SNOW IN THE HIGHEST TERRAIN OF THE POCONOS. IRONICALLY
THE CLOUD COVER (AND SOME WIND) WITH THE APPROACHING SHORT WAVE WE
SHOULD BE TOO CLOUDY FOR FROST/FREEZE CONCERNS.

A BLUSTERY OCTOBER SUNDAY IS PREDICTED. ONE LAST CHANNELIZED SHORT
WAVE HAS TO MOVE THROUGH DURING THE MORNING AND THEN MOSTLY SUNNY
SKIES SHOULD PREVAIL. EXCEPTION MAY BE OUR POCONOS WHERE FORECAST
SOUNDINGS ARE SHOWING STRATOCU REMAINING TRAPPED UNDERNEATH A
SUBSIDENCE INVERSION. THE DIRECTION/LOCATION OF THE SURFACE HIGH IS
NOT THE BEST FOR BRINGING SUNNY SKIES BACK TO OUR NORTHERN CWA. MAX
TEMPS CLOSE TO CONTINUITY AND 10 TO 15 DEGREES LOWER THAN SATURDAY.
LIKE LOWER MET GUIDANCE AS GFS PREDICTED 925MB/850MB TEMPS SUPPORT
THEM.

SUNDAY NIGHT STILL HAS THE POTENTIAL TO BE A FROSTY NIGHT. MODEL
SOUNDINGS ARE BRINGING SOME CIRRUS LEVEL MOISTURE BACK INTO OUR
CWA. NOT CONFIDENT WITH LONG NIGHTS THAT THEY WILL SAVE THE FROST
NIGHT AND WE KEPT MIN TEMPS CLOSE TO CONTINUITY. WE CURBED OUR
ENTHUSIASM FOR A ROBUST THERMAL RECOVERY ON MONDAY BECAUSE OF THE
PREDICTED WAA RETURN FLOW MOISTURE/CLOUDS.

CHANGES TO THE REST OF THE LONG TERM WAS IN A PESSIMISTIC DIRECTION
WITH GREATER CONSENSUS OF A MILLER B SECONDARY DEVELOPMENT CLOSER TO
THE COAST. THE INITIAL LOW AND COLD FRONT COULD TRIGGER SHOWERS ON
MONDAY NIGHT. AFTER THAT PRECIPITATION ASSOCIATED WITH 2NDRY
DEVELOPMENT COULD BRING MORE RAIN INTO OUR CWA ON TUESDAY AND
TUESDAY NIGHT. WRAP AROUND/DEFORMATION ZONE PRECIPITATION COULD HEAD
WEST INTO OUR CWA WEDNESDAY INTO WEDNESDAY NIGHT AND POSSIBLY
LINGERING INTO THURSDAY AS THE CLOSED UPPER LOW CAPTURES THE SURFACE
SYSTEM AND BOTH TRUNDLE EASTWARD THROUGH THE REST OF THE LONG TERM.
HIGHEST CHANCES ARE IN THE NORTHEASTERN PART OF OUR CWA LEANING
TOWARD THE CAN GGEM/ECMWF CONSENSUS. WITH THE SURFACE HIGH PRESSURE
NESTLED IN NEARBY CANADA, A RATHER PROLONGED AND RAW NORTH TO
NORTHEAST WIND FLOW IS ALSO EXPECTED. THERMALLY WE ARE SLIGHTLY
WARMER THAN LAST NIGHT, SO HARDLY ANY SNOW IS INCLUDED. BUT,
TEMPERATURES SHOULD BE AT OR BELOW SEASONAL LEVELS THROUGH THE
PERIOD. MORE IN THE DAYS AHEAD. WITH THE NEW MOON APPROACHING WE
WILL ALSO HAVE TO KEEP AN EYE ON THE TIDES.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THERE WILL BE AREAS OF FOG ACROSS THE REGION EARLY THIS MORNING...
ESPECIALLY ACROSS KRDG/KABE TERMINALS AND ALSO SOME AROUND
KMIV/KACY. THE OTHER TERMINALS WILL HAVE SOME FOG ALSO...BUT THE
VSBYS WILL PROBABLY NOT GET TOO LOW. AMDS EXPECTED WITH VARIABLE FOG
CONDITIONS THIS MORNING. WINDS LIGHT MOSTLY WRLY.

THE BALANCE OF TODAY WILL FEATURE VFR CONDITIONS AT THE TERMINALS
WITH SOME SCT DAYTIME CU/SC. WE HAVE KEPT THE TEMPO GROUP FOR AN
AFTER CIG (VFR) AT KRDG AND KABE. WINDS WILL BE WRLY THIS MORNING
THEN BECOME SWRLY THIS AFTERNOON. TONIGHT...VFR WITH LIGHT S OR SW
WINDS.

OUTLOOK...
SATURDAY THROUGH SUNDAY NIGHT...MAINLY VFR. WEST TO NORTHWEST WINDS
AROUND 15 KNOTS WITH GUSTS TO 25 KNOTS BOTH DAYS, HOWEVER LIGHTER
BOTH NIGHTS.

MONDAY...VFR.

MONDAY NIGHT AND TUESDAY...POSSIBLE SUB-VFR CONDITIONS DEVELOPING
MONDAY NIGHT AND MORE LIKELY ON TUESDAY.

&&

.MARINE...
SCA FLAG WHICH WAS FOR HAZARDOUS SEAS WILL BE CONVERTED TO A GENERIC
SCA FLAG WITH THE 330 AM CWF PACKAGE. SEAS WILL CONTINUE MOSTLY 5 TO
6 FT TODAY AND THEN INCREASE A LITTLE TONIGHT. WINDS WILL BE WRLY
THIS MORNING AROUND 10 KTS...THEN SHIFT SW THIS AFTERNOON AND
INCREASE TO 15 TO 20 KNOTS OVERNIGHT. SCA GUSTS WILL DEVELOP
TONIGHT. WINDS AND SEAS OVER DEL BAY WILL FOLLOW THE SAME
TRENDS...BUT WINDS AND SEAS WILL REMAIN BELOW SCA THRESHOLDS. DRY
WEATHER IS EXPECTED TODAY AND TONIGHT.

OUTLOOK...
SATURDAY AND SATURDAY NIGHT...THE SMALL CRAFT ADVISORY HAS BEEN
EXTENDED ON THE OCEAN THROUGH SATURDAY NIGHT. THIS WILL FEATURE
BOTH WINDS AND SEAS MEETING CRITERIA. A SMALL CRAFT ADVISORY WAS
ALSO ISSUED FOR DELAWARE BAY STARTING SATURDAY AFTERNOON AND MORE
CONFIDENT ABOUT REACHING THE WIND CRITERIA SATURDAY NIGHT.

SUNDAY AND SUNDAY NIGHT...SMALL CRAFT ADVISORY CONDITIONS SHOULD
CONTINUE SUNDAY BEFORE WINDS DIMINISH LATE SUNDAY AFTERNOON AND
SUNDAY EVENING, FIRST ON DELAWARE BAY AND LATER ON THE OCEAN. SEAS
ON THE OCEAN SHOULD ALSO SUBSIDE BELOW SMALL CRAFT ADVISORY
CRITERIA BY SUNDAY NIGHT. AN EXTENSION OF THE PRESENT ADVISORY
MAY BE NEEDED.

MONDAY AND TUESDAY...SUB SMALL CRAFT ADVISORY CONDITIONS EXPECTED.
OVERNIGHT TUESDAY WE WILL BE COMING CLOSE TO HEADLINES AGAIN AS THE
SECONDARY LOW PRESSURE SYSTEM STARTS TO DEVELOP.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ450>455.
     SMALL CRAFT ADVISORY FROM 2 PM SATURDAY TO 6 AM EDT SUNDAY FOR
     ANZ430-431.

&&

$$
SYNOPSIS...GIGI/GORSE
NEAR TERM...O`HARA
SHORT TERM...O`HARA
LONG TERM...GIGI
AVIATION...GIGI/GORSE/O`HARA
MARINE...GIGI/GORSE/O`HARA






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