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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 301137
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
637 AM EST FRI JAN 30 2015

.SYNOPSIS...
LOW PRESSURE AND AN ASSOCIATED COLD FRONT WILL MOVE THROUGH THIS
MORNING. AN ARCTIC COLD FRONT WILL FOLLOW THIS AFTERNOON AS THE
LOW RAPIDLY DEEPENS OFF THE NEW ENGLAND COAST. HIGH PRESSURE WILL
BUILD IN TONIGHT INTO SATURDAY...THEN PASS TO THE SOUTH SATURDAY
NIGHT. ANOTHER COLD FRONT WILL MOVE THROUGH ON SUNDAY...AND LOW
PRESSURE WILL PASS TO THE SOUTH ON MONDAY. HIGH PRESSURE WILL
RETURN THROUGH MID WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WEAK LOW PRESSURE AND COLD FRONT IS POISED TO MOVE THROUGH THE
AREA. THIS INCIPIENT WEAK LOW WILL GO ON TO BECOME A STRONG OCEAN
STORM EAST OF NEW ENGLAND. BANDS OF SNOW AND RAIN SHOWERS HAVE
DEVELOPED ALONG AND AHEAD OF THE FRONT AND LOOK TO SPREAD MAINLY
ACROSS LONG ISLAND AND SOUTHERN CT THIS MORNING. THIS WOULD BRING
AN ADDITIONAL COATING TO AN INCH OF ACCUMULATION ON TOP OF ANY
PRIOR LIGHT ACCUMULATION OVERNIGHT. ANY ISOLATED RAIN SHOWERS MAY
RESULT IN SOME LIGHT ICING. AGAIN THIS IS EXPECTED TO BE ISOLATED.

THE ARCTIC COLD FRONT WAS APPROACHING CENTRAL PA/NY...AND MAY
ALSO BE ACCOMPANIED BY SCT SNOW SHOWERS AS IT MOVES THROUGH THIS
AFTERNOON. NW WINDS WILL ALSO INCREASE AFTER ARCTIC FROPA AND
START TO USHER IN MUCH COLDER AIR...WITH HIGH TEMPS IN THE
LOWER/MID 20S DROPPING QUICKLY INTO THE 20S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SATURDAY/...
MULTIPLE WIND/COLD HAZARDS WILL EXIST DURING THIS TIME FRAME.
FIRST...THE HIGHER ELEVATIONS AND THE NYC METRO URBAN HEAT ISLAND
SHOULD BE THE FIRST AREAS TO SEE NW WINDS GUSTING AS HIGH AS 45-50
MPH TONIGHT VIA THE COMBO OF STRONG CAA AND A RAPIDLY TIGHTENING
PRESSURE GRADIENT AS THE LOW TO THE EAST BOMBS OUT S OF NOVA
SCOTIA INTO THE 980S. THESE STRONG WINDS SHOULD SPREAD TO THE REST
OF THE AREA LATE TONIGHT.

THE COMBO OF SUSTAINED WINDS 15-25 MPH...A LITTLE HIGHER THAN MOS
GUIDANCE...AND TEMPERATURES FALLING THRU THE TEENS AND INTO THE
SINGLE DIGITS INLAND...COLDER THAN THE COLDEST OF GFS/NAM MOS
GUIDANCE LOWS BY A COUPLE OF DEG...WILL RESULT IN HAZARDOUS WIND
CHILLS OF 15 TO 20 BELOW FROM LATE TONIGHT INTO SAT MORNING FOR
MOST INLAND SECTIONS...AND AROUND 10 BELOW FOR NYC AND URBAN
SECTIONS TO THE WEST...LONG ISLAND AND FAR SE CT.

SAT SHOULD BE A VERY COLD DAY DESPITE SUNSHINE...WITH HIGHS
STRUGGLING TO REACH 20 IN NYC AND LONG ISLAND...AND REMAINING IN
THE TEENS ELSEWHERE.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
GUSTY NW WINDS ABATE SATURDAY NIGHT AS DEEP LOW PRESSURE MOVES TO
THE CANADIAN MARITIMES. HIGH PRESSURE BUILDS TO THE SOUTH AS A COLD
FRONT APPROACHES FROM THE NW EARLY SUNDAY.

ATTENTION THEN TURNS TOWARD LOW PRESSURE THAT IS EXPECTED TO DEVELOP
AROUND THE MID MISSISSIPPI VALLEY AHEAD OF NORTHERN STREAM TROUGH.
AT THIS TIME...MODELS HAVE SHIFTED SLIGHTLY NORTH AS THEY TRACK THE
LOW FROM AROUND WEST VIRGINIA SUNDAY NIGHT TO OFF THE MID ATLANTIC
COAST MONDAY MORNING. IT APPEARS THAT THE LOW TRACKS SOUTH OF THE
AREA...THEN JUST SE OF THE 40N/70W BENCHMARK MONDAY AFTERNOON.

STILL PLENTY OF UNCERTAINTY AS MAIN ENERGY JUST MOVING INTO WESTERN
CANADA...AND RUN TO RUN SHIFTS IN TRACK HAVE BEEN OBSERVED.
HOWEVER...WILL BOOST POPS INTO THE LIKELY CATEGORY FOR MUCH OF THE
CWA...WITH HIGHEST POPS SOUTHERN PORTION...LOWER TO THE NORTH. ECMWF
AND GFS OUTPUT AT LEAST A HALF INCH OF MEASURABLE. BASED ON THIS
MODEL RUN...AGREE WITH PREVIOUS FORECAST OF A GENERAL 4 TO 8 INCHES
OF SNOW IN THIS PROGRESSIVE STORM...ALTHOUGH MAY UP THAT BY AN INCH
OR TWO ON THE LOW AND HIGH END...PERHAPS 5 TO 10. HOWEVER...ANY
SHIFT TO THE SOUTH...WHICH IS CERTAINLY POSSIBLE...WILL RESULT IN
LOWER SNOW AMOUNTS/CHANCES FOR PRECIP.

THEREAFTER...ARCTIC AIR MOVES IN BEHIND THE LOW AS HIGH PRESSURE
THAT ORIGINATES FROM THE CANADIAN PRAIRIES BUILDS ACROSS MID WEST
AND TOWARD THE EASTERN SEABOARD BY TUESDAY.

DRY WEATHER RETURNS WITH MUCH UNCERTAINTY FOR MID TO LATE WEEK. THE
QUESTION IS WHETHER OR NOT SOUTHERN STREAM PHASES WITH NORTHERN
STREAM TROUGH SOMETIME WED NIGHT OR THURSDAY. THIS WOULD RESULT IN
CLIPPER TYPE FRONT APPROACHING FROM THE W WITH POSSIBLE LOW PRESSURE
DEVELOPMENT WELL TO THE SOUTH TRACKING OFF THE EAST COAST.
AGAIN...ECMWF AND GFS DIFFER WITH TIMING AND STRENGTH...SO WILL CAP
POPS AT CHANCE FOR NOW LATE WED THROUGH THURSDAY.

TEMPS WERE A GRIDDED MOS/MAV AND MET BLEND SAT NIGHT AND
SUNDAY...WITH GRIDDED MOS AND WPC NEXT WEEK. OVERALL...COLD WEATHER
WILL PREVAIL WITH BELOW OR MUCH BELOW NORMAL TEMPS ON AVERAGE.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
LOW PRES PASSES THROUGH THE REGION THIS MORNING AND INTENSIFIES OVER
THE WESTERN ATLANTIC WATERS.

SNOW IS TAPERING OFF AS IT APPROACHES THE NORTHEAST...BUT CANNOT
RULE OUT A FEW LINGERING LIGHT SNOW SHOWERS. WILL TEMPO MVFR CONDS
AS THE COLD FRONT SWINGS THROUGH THE REGION.

ANY SUB-VFR CONDS LIFT BY EARLY AFTERNOON.

SW 10 KT OR LESS WILL SHIFT TO THE NW (AROUND OR JUST TO THE RIGHT
OF 310 MAG) IN THE AFTERNOON AND INCREASE TO AROUND 15 KT WITH GUSTS
AROUND 25 KT. TONIGHT THROUGH SATURDAY MORNING...WINDS INCREASE
FURTHER TO 20-25 KT WITH 35-40 KT GUSTS.

...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: AMDS LIKELY FOR TIMING OF WIND SHIFT AND
TIMING OF WIND SPEEDS...WHICH MAY BE OFF BY AN HOUR OR SO. AMDS ALSO
LIKELY FOR TIMING OF -SN AND TIMING OF CONDS IMPROVING TO VFR.

KLGA FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF WIND SHIFT AND
TIMING OF WIND SPEEDS...WHICH MAY BE OFF BY AN HOUR OR SO. AMDS ALSO
LIKELY FOR TIMING OF -SN AND TIMING OF CONDS IMPROVING TO VFR.

KEWR FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF WIND SHIFT AND
TIMING OF WIND SPEEDS...WHICH MAY BE OFF BY AN HOUR OR SO. AMDS ALSO
LIKELY FOR TIMING OF -SN AND TIMING OF CONDS IMPROVING TO VFR.

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES
SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KTEB FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF WIND SHIFT AND
TIMING OF WIND SPEEDS...WHICH MAY BE OFF BY AN HOUR OR SO. AMDS ALSO
LIKELY FOR TIMING OF -SN AND TIMING OF CONDS IMPROVING TO VFR.

KHPN FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF WIND SHIFT AND
TIMING OF WIND SPEEDS...WHICH MAY BE OFF BY AN HOUR OR SO. AMDS ALSO
LIKELY FOR TIMING OF -SN AND TIMING OF CONDS IMPROVING TO VFR.

KISP FCSTER COMMENTS: AMDS LIKELY FOR TIMING OF WIND SHIFT AND
TIMING OF WIND SPEEDS...WHICH MAY BE OFF BY AN HOUR OR SO. AMDS ALSO
LIKELY FOR TIMING OF -SN AND TIMING OF CONDS IMPROVING TO VFR.

.OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
.SATURDAY...VFR. NW WINDS 35-40 KT...DIMINISHING LATE.
.SATURDAY NIGHT...VFR. NW WIND G 20-30KT POSSIBLE EARLY.
.SUNDAY...VFR. NW WIND G15-20KT POSSIBLE.
.SUNDAY NIGHT-MONDAY..CHANCE OF SNOW WITH IFR CONDITIONS. NE-N
WIND G25-35KT POSSIBLE.
.MONDAY NIGHT...BECOMING VFR FROM W TO E AS ANY SNOW COMES TO AN
END. N-NW WIND G20-25KT POSSIBLE.
.TUESDAY...VFR.

&&

.MARINE...
SCA CONDS DEVELOPING ON THE OCEAN ATTM IN SW FLOW AHEAD OF WEAK
LOW PRESSURE AND AN ASSOCIATED COLD FRONT WILL INCREASE TO NW
GALES ON ALL WATERS BY LATE AFTERNOON FOLLOWING AN ARCTIC COLD
FROPA. GUSTS ON THE OCEAN COULD APPROACH STORM FORCE LATE TONIGHT
INTO SAT MORNING. THE COMBO OF STRONG WINDS AND COLD WATER TEMPS
FROM THE MID 30S TO LOWER 40S WILL ALSO RESULT IN AT LEAST
MODERATE FREEZING SPRAY DURING THIS TIME FRAME. THERE IS A CHANCE
FOR HEAVY FREEZING SPRAY ON LI SOUND...NY HARBOR AND THE NEAR
SHORE OCEAN WATERS WHERE SST IS ONLY IN THE MID/UPPER 30S...AND A
HEAVY FREEZING SPRAY WARNING MAY EVENTUALLY BE REQUIRED FOR THOSE
WATERS.

GUSTY WINDS WILL DIMINISH SATURDAY NIGHT INTO SUNDAY. SEAS WILL
RESPOND BY SUBSIDING THROUGH THIS TIME FRAME. SOME 5-FOOTERS MAY
CLIP THE EASTERNMOST OCEAN WATERS S OF MONTAUK INTO SUNDAY...BUT
SUB SCA CONDITIONS ARE LIKELY ACROSS THE WATERS SUNDAY.

HOWEVER...THIS WILL BE BRIEF AS WINDS INCREASE AGAIN AHEAD OF LOW
PRESSURE SUNDAY NIGHT AND MONDAY. THE LOW IS EXPECTED TO PASS TO THE
SOUTH MONDAY...MOVING WELL TO THE EAST MONDAY NIGHT. HIGH PRESSURE
BUILDS IN TUESDAY.

STRONG SCA CONDITIONS MONDAY WILL IMPROVE BY TUESDAY AS THE HIGH
BUILDS.

&&

.HYDROLOGY...
TOTAL QPF OF 1-2 TENTHS OF AN INCH LIQUID EQUIVALENT EXPECTED
THROUGH THIS AFTERNOON...WITH MOST OF THE PRECIPITATION FALLING
AS SNOW.

LOW PRESSURE SUNDAY NIGHT AND MONDAY WILL BRING THE POTENTIAL FOR
QPF OF 1/2 TO 1 INCH LIQUID EQUIVALENT...ALL IN THE FORM OF SNOW.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST SATURDAY
     FOR CTZ005>012.
     WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SATURDAY
     FOR CTZ005>007-009-010.
NY...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST SATURDAY
     FOR NYZ067>075-078>081-176>179.
     WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SATURDAY
     FOR NYZ067>071.
NJ...WIND ADVISORY FROM 4 PM THIS AFTERNOON TO 4 PM EST SATURDAY
     FOR NJZ002-004-006-103>108.
     WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST SATURDAY
     FOR NJZ002-004-103-104.
MARINE...FREEZING SPRAY ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST
     SATURDAY FOR ANZ330-335-338-340-345-350-353-355.
     GALE WARNING FROM 1 PM THIS AFTERNOON TO 6 PM EST SATURDAY FOR
     ANZ330-335-338-340-345-350-353-355.
     SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR ANZ350-
     353-355.

&&

$$
SYNOPSIS...GOODMAN/PW
NEAR TERM...GOODMAN/PW
SHORT TERM...GOODMAN
LONG TERM...PW
AVIATION...MPS/NV
MARINE...GOODMAN/PW
HYDROLOGY...GOODMAN/PW