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000
FXUS61 KOKX 100912
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
412 AM EST TUE DEC 10 2013

.SYNOPSIS...
A COASTAL LOW TRACKS TO THE SOUTHEAST OF LONG ISLAND TODAY. HIGH
PRESSURE THEN BUILDS IN FROM THE WEST TONIGHT...FOLLOWED BY A COLD
FRONT APPROACHING ON WEDNESDAY. THE COLD FRONT WILL MOVE ACROSS THE
AREA WEDNESDAY NIGHT...WITH HIGH PRESSURE BUILDING IN FROM THE
SOUTH AND WEST THROUGH THE END OF THE WEEK. A COASTAL STORM WILL
LIKELY IMPACT THE REGION THIS WEEKEND...WITH HIGH PRESSURE
RETURNING EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MSAS ANALYSIS HAD A BROAD 1014 LOW OVER THE SOUTHERN
APPALACHIANS...WITH PRESSURE FALLS INDICATING IT WILL CONTINUE TO
TRACK TO THE NORTHEAST. THE LOW WILL DEEPEN AS IT TRACKS NE IN
RESPONSE TO AN APPROACHING 700-500 HPA TROUGH. CONSENSUS OF THE
MODELS TAKES THE LOW TO THE SE OF THE 40N/70W BENCHMARK BY EARLY
THIS AFTERNOON. SO THIS...COUPLED WITH ONGOING LOW LEVEL COLD AIR
ADVECTION WILL YIELD A P-TYPE OF SNOW ACROSS THE ENTIRE CWA...WITH
THE POSSIBLE EXCEPTION OF MAYBE 1-2 HOURS THIS MORNING OVER THE TWIN
FORKS WHERE SOME RAIN MIGHT BE MIXED IN BEFORE TEMPERATURES WETBULB
TO FREEZING.

TEMPERATURES ARE CRITICAL TO THIS FORECAST - EXPECT GENERALLY SLOWLY
FALLING TEMPERATURES THIS MORNING ONCE THE PRECIPITATION BEGINS...AND
THIS WILL CONTINUE INTO THIS AFTERNOON WITH THE WET-BULBING OF
TEMPERATURE - ESPECIALLY NOTING THAT LOWER DEWPOINT AIR IS BEING
ADVECTED IN THE LOWER LEVELS. THIS WILL PLACE NORTHERN ZONES IN THE
MID TO UPPER 20S AND SOUTHERN ZONES AROUND 30. THIS TEMPERATURE FALL
OFF WILL ALLOW FOR RATIOS OF AROUND 12:1 ACROSS SOUTHERN AREAS AND
15-20:1 INLAND.

RAP/NAM/GFS/SREF/ECMWF ALL SHOW AN AREA OF FAIRLY STRONG
FRONTOGENESIS FROM 700-500 HPA CROSSING THE AREA THIS MORNING TO
EARLY AFTERNOON...WITH THE CORE IF IT TRACING FROM JUST W OF NYC ON
NE INTO S CT.

GIVEN THE RATIO AND THE BANDING - APPEARS EVEN WITH QPF AROUND 1/3
OF AN INCH ACROSS SOUTHERN ZONES + AND AROUND .2" ACROSS NORTHERN
ZONES...EXPECT A 3-5" SNOWFALL ACROSS THE ENTIRE CWA WITH LOCALLY
HIGHER AMOUNTS UNDER STRONGER SNOW BANDS. THE SNOW WILL MOVE THROUGH
THE REGION FAIRLY QUICKLY...MAINLY OVER A 6-8 HOUR PERIOD FROM
13-21Z.

AS A RESULT HAVE EXPANDED THE WINTER WEATHER ADVISORY TO THE ENTIRE
CWA AND ADJUSTED ITS TIMING. FOR NE NJ AND THE WESTERN LOWER HUDSON
VALLEY - IT IS IN EFFECT FROM 11Z-21Z. FOR NYC/LONG ISLAND/EASTERN
LOWER HUDSON VALLEY/S CT THE ADVISORY WILL BE IN EFFECT FROM
12Z-22Z. THE HEAVIEST SNOW WILL OCCUR DURING THE SNOWBANDS WITH THE
AFOREMENTIONED 500-700 HPA FRONTOGENESIS MAXIMUM FROM 14-19Z FROM SW
TO NE ACROSS THE AREA.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
CONDITIONS QUICKLY CLEAR OUT ACROSS MOST OF THE AREA THIS EVENING AS
THE LOW PULLS OUT WITH WEAK RIDGING BUILDING IN ALOFT THE EXCEPTION
WILL BE LAKE EFFECT CLOUDS SETTING UP ACROSS FAR NW AREAS. BLUSTERY
WINDS TONIGHT ACROSS ALL BUT WESTERN INTERIOR AREAS IN THE WAKE OF
THE STORM...WITH GUSTS OF 20-30 MPH. USED THE MINIMUM OF MAV/MET/NAM
2-METER TEMPERATURES FOR LOWS - WITH VALUES AROUND 10 DEGREES BELOW
NORMAL. DID NOT UNDERCUT GUIDANCE WITH SNOW COVER DUE TO WINDS BEING
A LIMITING FACTOR. WIND CHILLS OVERNIGHT WILL RANGE FROM 5 TO 15
DEGREES - COLDEST N OF NYC AND WARMEST OVER EASTERN LONG ISLAND.

WEAK RIDGING EXITS TO THE EAST WEDNESDAY WITH A WSW FLOW SETTING UP
ALOFT. THIS SHOULD KEEP MOST IF NOT ALL LAKE EFFECT FLURRIES/-SHSN
TO THE N OF THE AREA. MIXING WILL BE LIMITED TO AROUND 925-900 HPA
SO HIGHS WILL STRUGGLE  TO REACH THE 30 DEGREE MARK IN MOST
LOCATIONS...WITH COASTAL SE CT AND THE TWIN FORKS STRUGGLING TO
REACH FREEZING. THESE HIGHS ARE CONSISTENT WITH A BLEND OF MIXING
DOWN FROM 925 HPA...EXCEPT 900 HPA WELL INLAND...WITH NAM 2-METER
TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE...AND ARE AROUND 15
DEGREES BELOW NORMAL. WIND CHILLS WEDNESDAY WILL MAINLY BE IN THE
TEENS...WITH SOME AROUND 20 ACROSS COASTAL SE CT AND THE TWIN FORKS.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
THE H5 FLOW ACROSS THE EASTERN US WILL START WITH A BROAD TROUGH AND
BECOME ZONAL BY THE WEEKEND. MEANWHILE A SPLIT FLOW OUT WEST WILL
PHASE WITH TIME AS THE NORTHERN BRANCH DIGS FROM THE PAC NW TO THE
ROCKIES AND PLAINS STATES. THIS PHASING ENERGY WILL BE THE AREA TO
WATCH THROUGH THE REMAINDER OF THE WEEK AS SIGNALS FOR A COASTAL
STORM THIS WEEKEND ARE APPARENT.

AT THE SFC...A COLD FRONT WILL TRAVERSE THE AREA WED NIGHT. DEEP
LAYERED MOISTURE IS LACKING...THEREFORE EXPECT IT TO PASS DRY. A FEW
LAKE EFFECT FLURRIES MAY MAKE IT INTO FAR NW ORANGE COUNTY. COLD
WEATHER WILL CONTINUE THROUGH THE END OF THE WEEK WITH HIGHS
STRUGGLING TO REACH THE FREEZING MARK ON THU (H85 TEMPS AROUND
-15C). SIDED WITH THE COLDER GUIDANCE WITH THE SNOWPACK EXPECTED TO
REMAIN ON THE GROUND. LOWS WED NIGHT WILL GENERALLY BE IN THE LOWER
TEENS INLAND TO AROUND 20 IN METRO NY/NJ. THU NIGHT WILL BE A TAD
COLDER WITH LESS CLOUD COVER WITH TEENS AT THE COAST AND SINGLE
DIGITS INLAND. WIND CHILLS BOTH NIGHTS WILL DROP INTO THE SINGLE
DIGITS ACROSS THE AREA...AND COULD FALL BELOW ZERO THU NIGHT ACROSS
INTERIOR ZONES. CONDS WILL REMAIN DRY THROUGH FRI WITH HIGH PRES
NOSING IN FROM THE S AND W.

AS FOR THE WEEKEND SYSTEM...THE INITIAL SFC LOW ASSOCIATED WITH THE
SOUTHERN BRANCH OF THE JET STREAM IS FORECAST TO DEVELOP IN THE LEE
OF THE ROCKIES AND MOVE ACROSS THE SOUTHERN PLAINS FRI AND FRI
NIGHT. AS THE NORTHERN STREAM ENERGY PHASES WITH IT AND MOVES
TOWARDS THE MID ATLANTIC COAST...THE SYSTEM WILL STRENGTHEN AND
TRACK FROM THE MID ATLANTIC COAST JUST S AND E OF LI BEFORE LIFTING
TOWARDS NOVA SCOTIA.

THE DEVIL IS IN THE DETAILS AND THERE IS A 6-12 HOUR DIFFERENCE IN
THE TIMING BETWEEN THE OPERATIONAL EC...CMC AND GFS. THE TRACK IS
THE MOST CONSISTENT ASPECT OF THE SYSTEM AND WITH A DECENT HIGH TO
THE NE IT SHOULD BE COLD ENOUGH AT THE ONSET FOR SNOW WITH A GRADUAL
WARMING OF THE ATMOSPHERE. THE TIMING AND EXTENT OF THE CHANGEOVER
STILL NEEDS TO BE RESOLVED. THE GFS IS MUCH WARMER THAN THE EC TO
START WHICH IS A KNOWN BIAS OF THE MODEL. IT IS LIKELY ERODING THE
COLD AIR TOO QUICKLY. THIS WILL ULTIMATELY HAVE IMPACTS ON
P-TYPE...SO HAVE LOW CONFIDENCE IN THE DETAILS OF THE CURRENT
FORECAST.

HIGH PRES THEN BUILDS TOWARDS THE AREA FOR THE START OF THE NEW WORK
WEEK WITH DRY BUT COLD AND POTENTIALLY GUSTY CONDS.

&&

.AVIATION /09Z TUESDAY THROUGH SATURDAY/...
LOW PRESSURE WILL PASS TO THE SOUTH TODAY AND BRING A MODERATE
SNOWFALL.

VFR AT MOST PLACES TO START WITH WSW WINDS 5-10 KT VEERING W.

WINDS WILL VEER NW TODAY BUT SHOULD NOT INCREASE NOTICEABLY UNTIL
EVENING. LIGHT SNOW WILL MOVE IN FROM 12Z-14Z. PERIOD OF MODERATE
SNOW EXPECTED WITH LIFR VSBY 15-19Z.

SNOWFALL TOTALS RIGHT LOOK TO BE BETWEEN 2-5 INCHES ACROSS THE
BOARD. A NARROW CORRIDOR OF SW-NE ORIENTED HEAVIER SNOW BANDS IS
EXPECTED AND COULD PRODUCE LOCALLY HIGHER AMTS OF 6-7 INCHES.
THESE BANDS APPEAR MOSTLY LIKELY TO SET UP DIRECTLY OVER OR JUST
NORTH/WEST OF THE NYC METRO TERMINALS.

...NY METRO ENHANCED AVIATION WEATHER SUPPORT...

DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT:  HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)

KJFK FCSTER COMMENTS: AMD LIKELY TO FINE TUNE TIMING OF SNOW AND
ASSOCIATED IFR/LIFR CONDS.

KLGA FCSTER COMMENTS: AMD LIKELY TO FINE TUNE TIMING OF SNOW AND
ASSOCIATED IFR/LIFR CONDS.

KEWR FCSTER COMMENTS: AMD LIKELY TO FINE TUNE TIMING OF SNOW AND
ASSOCIATED IFR/LIFR CONDS.

KTEB FCSTER COMMENTS: AMD LIKELY TO FINE TUNE TIMING OF SNOW AND
ASSOCIATED IFR/LIFR CONDS.

KHPN FCSTER COMMENTS: AMD LIKELY TO FINE TUNE TIMING OF SNOW AND
ASSOCIATED IFR/LIFR CONDS.

KISP FCSTER COMMENTS: AMD LIKELY TO FINE TUNE TIMING OF SNOW AND
ASSOCIATED IFR/LIFR CONDS.

.OUTLOOK FOR 06Z WED THROUGH SAT...
.LATE TONIGHT-WED...VFR. W WINDS G20-25KT.
.THU...VFR. W-NW G20KT.
.FRI...VFR.
.SAT...MVFR OR LOWER CONDITIONS WITH MIXED WINTRY PRECIP.

&&

.MARINE...
WINDS HAVE FALLEN BELOW SCA LEVELS ACROSS THE COASTAL OCEAN
WATERS...HOWEVER SEAS AT 44017 STILL AT 6 FT...SO WILL CONTINUE THE
SCA FOR ANZ350-353 THROUGH 6 AM...BUT WILL CANCEL FOR ANZ-355.

AFTER A LULL WITH SUB-SCA CONDITIONS THIS MORNING...WIND GUSTS
INCREASE LATE THIS AFTERNOON TO SCA LEVELS ON THE COASTAL OCEAN
WATERS LATE THIS AFTERNOON. GUSTS TO GALE FORCE ARE EXPECTED TONIGHT
ON THE COASTAL OCEAN WATERS...WITH GUSTS TO SCA LEVELS ELSEWHERE IN
THE WAKE OF THE DEPARTING LOW. THE SCA LEVEL GUSTS WILL LIKELY
CONTINUE ON ALL WATERS WEDNESDAY.

AS A RESULT HAVE ISSUED A GALE WARNING FOR THE COASTAL OCEAN WATERS
FOR TONIGHT AND A SMALL CRAFT ADVISORY FOR THE REMAINDER OF THE
WATERS. WITH CONFIDENCE NOT QUITE AT 80 PERCENT...OPTED NOT TO
EXTEND THE SCA INTO WEDNESDAY ON THE NON-OCEAN ZONES.

SCA MAY NEED TO BE CONTINUED INTO PART OF WED NIGHT WITH WINDS AND
SEAS DIMINISHING. AFTER A BRIEF LULL ON THU/THU NIGHT...CAA IS
EXPECTED TO BRING WINDS AND SEAS BACK UP WITH SCA LIKELY NEED ON AT
LEAST THE OCEAN WATERS FRI. CONDS THEN SHOULD REMAIN AT SUB-ADVSY
LEVELS UNTIL THE COASTAL SYSTEM THIS WEEKEND ALTHOUGH TIMING IS
UNCERTAIN AT THIS TIME. STRONG GALES ARE POSSIBLE ON THE BACKSIDE OF
THE SYSTEM.

&&

.HYDROLOGY...
WILL RECEIVE FROM .1 TO .4 INCHES OF LIQUID EQUIVALENT
TODAY...ALMOST ALL OF IT IN THE FORM OF SNOW. NO HYDROLOGIC ISSUES
ARE EXPECTED. IT SHOULD THEN BE DRY THROUGH FRIDAY.

THERE IS THE POTENTIAL FOR SIGNIFICANT PRECIPITATION THIS WEEKEND IN
ASSOCIATION WITH A COASTAL LOW PRES SYSTEM.

&&

.EQUIPMENT...
DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD
EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS
WEATHER RADIO STATION KWO35 REMAINS OUT OF SERVICE. THE NATIONAL
WEATHER SERVICE IS WORKING WITH SEVERAL U.S. GOVERNMENT AGENCIES
TO ISOLATE AND RESOLVE THIS TECHNICAL PROBLEM.

DURING THIS TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE
INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO
DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE
WEEKLY TESTS OF THE WARNING SYSTEM...AND TO DETERMINE IF THE
INTERFERENCE ISSUE HAS BEEN RESOLVED.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 5 PM EST
     THIS AFTERNOON FOR CTZ005>012.
NY...WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 5 PM EST
     THIS AFTERNOON FOR NYZ068-070>075-078>081-176>179.
     WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
     NYZ067-069.
NJ...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
     NJZ002-004-006-103>108.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
     WEDNESDAY FOR ANZ330-335-338-340-345.
     GALE WARNING FROM 6 PM THIS EVENING TO 6 AM EST WEDNESDAY FOR
     ANZ350-353-355.
     SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     ANZ350-353.

&&

$$

SYNOPSIS...24/MALOIT
NEAR TERM...MALOIT
SHORT TERM...MALOIT
LONG TERM...24
AVIATION...GOODMAN
MARINE...24/MALOIT
HYDROLOGY...24/MALOIT
EQUIPMENT...