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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 260535
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1235 AM EST MON JAN 26 2015

.SYNOPSIS...
LOW PRESSURE TRACKS INTO THE CENTRAL APPALACHIANS OVERNIGHT...THEN
TRANSITIONS TO A COASTAL LOW OFF THE MID ATLANTIC COAST BY MONDAY
EVENING. THIS COASTAL LOW WILL RAPIDLY DEEPEN...BECOMING A
DANGEROUS WINTER STORM AS IT TRACKS SLOWLY NORTH FROM THE MID
ATLANTIC COAST AND STALLS SOUTHEAST OF MONTAUK POINT LATE MONDAY
NIGHT INTO TUESDAY...THEN WEAKENS AND MOVES SLOWLY EAST TUESDAY
NIGHT. A WEAKER SYSTEM WILL PASS THROUGH THURSDAY NIGHT INTO
FRIDAY. HIGH PRESSURE WILL FOLLOW FOR SATURDAY...THEN A COLD FRONT
WILL MOVE THROUGH ON SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
MADE MINOR CHANGES TO REFLECT THE LATEST TRENDS IN OBSERVATIONS
AND GUIDANCE. FORECAST APPEARS ON TRACK.

UPPER TROUGH SLIDES EAST OF NEW ENGLAND OVERNIGHT WITH POLAR HIGH
SLIDING INTO NEW ENGLAND IN WAKE OF A WEAKENING ARCTIC FRONTAL
PASSAGE. LOWS GENERALLY DROPPING INTO THE TEENS INTERIOR AND 20S
COAST. THESE LOWS MAY BE TOO COLD DEPENDING ON HOW QUICKLY HIGH
CLOUDS STREAM IN. TEMPS SHOULD STABILIZE OVERNIGHT WITH INCREASING
CLOUDS AND INCREASING NE FLOW.

THEREAFTER...ALL EYES ON STRONG SHORTWAVE ENERGY DIVING THROUGH THE
MID MISSISSIPPI RIVER VALLEY THIS AFTERNOON AND INTO THE SE US
TONIGHT. THIS WILL HAVE LOW PRESSURE TRACKING ALONG THE
SOUTHEASTERN US TONIGHT...AND REACHING THE COAST BY MONDAY
MORNING...WITH POTENTIAL FOR LIGHT SNOW TO DEVELOP LATE SUN NIGHT
INTO MONDAY MORNING ACROSS AT LEAST FAR SW PORTIONS OF THE TRI-
STATE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY NIGHT/...
A LIFE THREATENING...HISTORIC WINTER STORM EXPECTED FROM LATE
MONDAY INTO TUESDAY...

NWP GUIDANCE CONTINUES TO BRING THE INGREDIENTS TOGETHER FOR A
DANGEROUS...HISTORIC BLIZZARD AS A SECONDARY LOW FORMS OFF THE
MID ATLANTIC COAST ON MON. THIS LOW WILL UNDERGO RAPID
INTENSIFICATION AS THE PARENT UPPER LOW CUTS OFF ALOFT NEAR THE
MID ATLANTIC MON NIGHT...STALLING SE OF MONTAUK LATE MON NIGHT
INTO TUE. MSLP DROPS NEARLY 30 MB IN 24 HR FROM MON AM TO TUE
AM... BEFORE GRADUALLY FILLING.

THIS WILL PLACE THE FORECAST AREA ON THE NW FLANK OF THE
LOW. AFTER LIGHT WARM ADVECTION SNOWFALL OF 1-3 INCHES DURING THE
DAYTIME HOURS MON IN ADVANCE OF THE SECONDARY LOW...A PROLONGED
PERIOD OF MDT-HEAVY SNOW EXPECTED IN THE DEFORMATION ZONE.
FOLLOWED 12Z NAM/ECMWF CLOSELY...WITH BOTH MODELS SUPPORTING QPF
UPWARDS OF 2 INCHES LIQUID EQUIVALENT...WITH THE HIGHEST AMOUNTS
NOW EXPECTED NOT ONLY ACROSS EASTERN LONG ISLAND/CT BUT ALSO
FARTHER WEST INTO SW CT AND THE NYC METRO AREA/WESTERN LONG
ISLAND...AS MODELS OFTEN DO NOT PLACE THE AREA OF MOST INTENSE MID
LEVEL FRONTOGENESIS FAR ENOUGH WEST. SNOWFALL RATES OF 2-4 INCHES
PER HOUR EXPECTED LATE MON NIGHT INTO TUE MORNING. MUCH OF THE
AREA SHOULD SEE AMOUNTS OF 20-30 INCHES...LOCALLY HIGHER WHERE
BEST MESOSCALE SNOW BANDING SETS UP.

IN ADDITION...THE DEEP LOW PRESSURE COMBINED WITH STRONG HIGH
PRESSURE TO THE NORTH AND WEST AND HEAVY FALLING/BLOWING SNOW WILL
CREATE BLIZZARD CONDITIONS ACROSS THE ENTIRE REGION. A BLIZZARD
WARNING IS NOW IN EFFECT...WITH POTENTIAL FOR SUSTAINED WINDS UP
TO 40 MPH ON LONG ISLAND...AND WIND GUSTS RANGING FROM 40 MPH
INLAND...TO 50-55 MPH MOST ELSEWHERE...TO 65 MPH ACROSS EASTERN
LONG ISLAND...WHERE A BRIEF HURRICANE FORCE GUST CANNOT BE RULED
OUT.

TEMPS DURING THE STORM WILL GENERALLY BE IN THE 20S...EXCEPT
FALLING TO 15-20 MON NIGHT INLAND. WIND CHILLS WILL BE MOSTLY IN
THE SINGLE DIGITS TO MID TEENS...BUT AS LOW AS ZERO TO 5 BELOW
ACROSS SOUTHERN CT.

THANKS TO ALL NEIGHBORING WFOS...ERH AND WPC FOR COLLABORATION
THIS AFTERNOON.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
A LINGERING SNOW SHOWER COULD OCCUR OVER FAR EASTERN AREAS WEDNESDAY
MORNING...OTHERWISE DRY WEATHER...CLEARING AND COLD WITH DIMINISHING
WINDS. WENT BELOW GUIDANCE FOR HIGHS TEMPS AS WELL AS OVERNIGHT
LOWS...CONSIDERING A DEEP SNOW PACK IN PLACE.

A HIGH PRESSURE RIDGE IS PROGGED TO BE RIGHT OVER US THURSDAY
MORNING. THE HIGH SHIFTS OFFSHORE...THEN LOW PRESSURE APPROACHING
FROM THE WEST COULD BRING LIGHT SNOW BY LATE IN THE DAY TO THE FAR
NW ZONES. THE CENTER OF THIS LOW IS FORECAST TO PASS NEAR OR THROUGH
THE CWA AT SOME POINT THURSDAY NIGHT INTO FRIDAY. WILL CONTINUE TO
CAP POPS AT CHANCE FOR THE ENTIRE AREA DURING THIS PERIOD...BUT MAY
NEED TO EVENTUALLY BUMP POPS UP. PRECIPITATION TYPE PROBABLY SNOW
FOR MOST OF THE AREA...BUT MIXED PRECIPITATION WOULD BE POSSIBLE
FOR SOME COASTAL AREAS.

HIGH PRESSURE BUILDS BACK IN ON SATURDAY WITH BELOW NORMAL
TEMPERATURES. A COLD FRONT OR TROUGH THEN MOVES THROUGH DURING
SUNDAY. MOISTURE LOOKS LIMITED...BUT WILL GO WITH SLIGHT CHANCE
POPS IN THE GRIDS FOR SNOW SHOWERS. TEMPS REMAINING BELOW NORMAL.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
** HIGH IMPACT SNOW AND WIND EVENT EXPECTED FROM LATE TODAY INTO
TUESDAY NIGHT **

LOW PRESSURE DEVELOPS EAST OF THE MID ATLANTIC COAST THIS MORNING
AND...THEN TRACKS TO A POSITION AROUND 175 MILES SOUTHEAST OF
MONTAUK POINT BY AROUND 6Z TUESDAY.

VFR...LOWERING TO MVFR BY AROUND 12-14Z FROM W TO E. IFR IN SNOW BY
15-18Z AND LIFR BY 18-21Z FROM W TO E. BLIZZARD CONDITIONS EXPECTED
AT KJFK/KLGA/KISP/KGON BY LATE THIS EVENING. 1-4" OF SNOW EXPECTED
BY 00Z...THEN 2-4 INCH AN HOUR RATES DEVELOP FROM SE TO NW STARTING
AROUND MIDNIGHT.

N WINDS VEER TO THE NE EARLY THIS MORNING. WINDS BECOME GUSTY BY
LATE MORNING WITH GUSTS UP TO 25-30KT BY MID-LATE AFTERNOON. WINDS
BACK TO THE NNE LATE TONIGHT...WITH GUSTS INCREASING TO 25-40KT
LOWEST FAR W TERMINALS AND STRONGEST FAR E TERMINALS.

.OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY...
.LATE MONDAY NIGHT-TUESDAY EVENING...LIFR OR LOWER CONDITIONS WITH
BLIZZARD CONDITIONS. NE-N WINDS G40-55 KT.
.LATE TUESDAY NIGHT...BECOMING VFR. NW WINDS G25-35KT.
.WEDNESDAY...VFR. NW WINDS G25-30KT POSSIBLE.
.WEDNESDAY NIGHT-THURSDAY...VFR.
.THURSDAY NIGHT-FRIDAY...MVFR OR LOWER CONDITIONS IN SNOW. SW WINDS
G25-40KT POSSIBLE.
-- End Changed Discussion --

&&

.MARINE...
MAIN CHANGE THIS PACKAGE WAS TO ISSUE STORM WARNING FOR THE SOUTH
SHORE BAYS FOR MONDAY NIGHT AND TUESDAY. WITH STORM FORCE GUSTS
FORECAST FOR THE COASTAL OCEAN WATERS AND FOR AT LEAST A PORTION
OF ADJACENT SUFFOLK COUNTY...IT MAKES SENSE THAT SIMILAR GUSTS
WILL OCCUR IN THE BODY OF WATER IN BETWEEN THE TWO.

OTHERWISE...ONLY MINOR ADJUSTMENTS MADE WITH THIS UPDATE...WITH
THE FORECAST AS A WHOLE APPEARING ON TRACK OUTSIDE OF THE
ADJUSTMENT NOTED ABOVE.

WINDS AND SEAS INCREASE ACROSS ALL WATERS ON MON AHEAD OF
APPROACHING LOW PRESSURE. GALE FORCE EASTERLY WIND GUSTS EXPECTED
ON THE OCEAN WATERS DURING THE DAY ON MON...RAMPING UP MON NIGHT
AS WINDS BACK NORTHERLY TO MINIMAL HURRICANE FORCE ON THE EASTERN
OCEAN WATERS LATE MON NIGHT INTO TUE MORNING...AND STORM FORCE
ELSEWHERE AND ALSO ON EASTERN LONG ISLAND SOUND AND THE BAYS OF
LONG ISLAND. THE EASTERN OCEAN WATERS MAY ALSO SEE SUSTAINED STORM
FORCE WINDS DURING THIS TIME.

WIND GUSTS SHOULD SUBSIDE BELOW GALE FORCE ON THE OCEAN WATERS
DURING WED...WITH ALL WATERS BELOW ADVISORY CRITERIA BY LATE WED
NIGHT. RELATIVELY TRANQUIL CONDITIONS WILL FOLLOW FOR THU INTO
THU NIGHT AS A HIGH PRESSURE RIDGE SHIFTS THROUGH. SCA CONDITIONS
ARE POSSIBLE AGAIN ON FRI...WITH A LOW PRESSURE SYSTEM AFFECTING
THE REGION.

&&

.HYDROLOGY...
A MAJOR SNOWSTORM EXPECTED FROM MON INTO TUE NIGHT...WITH LIQUID
EQUIVALENT AMOUNTS OF 1.5 TO 3 INCHES.

LIQUID EQUIVALENT PRECIPITATION AMOUNTS FOR THE SYSTEM MOVING
THROUGH THURSDAY NIGHT INTO FRIDAY IS CURRENTLY FORECAST TO BE
LIGHT...MOSTLY IN THE FORM OF SNOW.

ICE ON THE WALLKILL AND YANTIC RIVERS IS CAUSING MINOR
FLUCTUATIONS IN RIVER LEVELS AT THIS TIME.

&&

.TIDES/COASTAL FLOODING...
AN INTENSE COASTAL STORM WILL LIKELY BRING MODERATE COASTAL
IMPACTS TO PARTS OF THE COASTAL REGION WITH THE LATE MONDAY NIGHT
INTO EARLY TUESDAY MORNING HIGH TIDE. THIS WILL BRING POTENTIAL
FOR FLOODING OF VULNERABLE SHORE ROADS AND/OR ADJACENT PROPERTIES
DUE TO HEIGHT OF STORM TIDE AND/OR WAVE ACTION. SEVERAL SHORE ROAD
CLOSURES MAY BE NEEDED.

THE UNCERTAINTY WITH THE SURGE IS IN HOW QUICKLY WINDS TURN FROM
THE NE TO N. AN EARLIER VEERING OF WINDS TO THE N AHEAD OF HIGH
TIDE TYPICALLY REDUCES SURGE IN OUR REGION.

THE MOST LIKELY SURGE FOR COASTAL AREAS ALONG WESTERN LONG ISLAND
SOUND IS 3 TO 4 FT OF SURGE ABOVE ASTRONOMICAL TIDE. A LOW
PROBABILITY OF 4 TO 4 1/2 FT SURGE ABOVE ASTRONOMICAL TIDE EXISTS.

THE MOST LIKELY SURGE FOR COASTAL AREAS ALONG EASTERN LONG ISLAND
SOUND AND EASTERN LONG ISLAND SOUND IS 2 1/2 TO 3 1/2 FT OF SURGE
ABOVE ASTRONOMICAL TIDE. A LOW PROBABILITY OF 3 1/2 TO 4 FT SURGE
ABOVE ASTRONOMICAL TIDE EXISTS.

THE MOST LIKELY SURGE FOR NY/NJ COASTAL AREAS ALONG NEW YORK HARBOR
AND THE SOUTH SHORE BAYS OF LI/NYC IS 2 1/2 TO 3 1/2 FT OF SURGE
ABOVE ASTRONOMICAL TIDE. A LOW PROBABILITY OF 3 TO 4 FT SURGE
ABOVE ASTRONOMICAL TIDE EXISTS.

SIGNIFICANT BEACH EROSION AND WASHOVERS ARE EXPECTED ALONG OCEAN
FACING BARRIER BEACHES OF LONG ISLAND DUE TO 10 TO 15 FT WAVES AND
HIGH STORM TIDE. A FEW EXPOSED WATER FRONT STRUCTURES MAY BE
DAMAGED.

HIGH WAVES AND HIGH STORM TIDE WILL ALSO CAUSE BEACH EROSION ALONG
NORTH FACING SHORELINES OF LONG ISLAND SOUND AND ALONG THE TWIN
FORKS. A FEW EXPOSED WATER FRONT STRUCTURES MAY BE DAMAGED.

&&

.CLIMATE...
THIS BLIZZARD HAS THE POTENTIAL TO PRODUCE THE LARGEST SINGLE-
STORM SNOWFALL IN NYC HISTORY. HERE ARE THE CURRENT TOP TEN
SNOWFALLS FOR THE CITY...


AMOUNT        DATES

26.9          FEB 11-12 2006
25.8          DEC 26-27 1947
21.0          MAR 12-13 1888
20.9          FEB 25-26 2010
20.2          JAN 7-8   1996
20.0          DEC 26-27 2010
19.8          FEB 16-17 2003
19.0          JAN 26-27 2011
18.1          JAN 22-24 1935 AND MARCH 7-8 1941
18.0          DEC 26    1872

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...COASTAL FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING
     FOR CTZ011-012.
     BLIZZARD WARNING FROM 1 PM THIS AFTERNOON TO MIDNIGHT EST
     TUESDAY NIGHT FOR CTZ005>012.
     COASTAL FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING
     FOR CTZ009-010.
NY...COASTAL FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING
     FOR NYZ079-081.
     BLIZZARD WARNING FROM 1 PM THIS AFTERNOON TO MIDNIGHT EST
     TUESDAY NIGHT FOR NYZ067>075-078>081-176>179.
     COASTAL FLOOD WATCH LATE TONIGHT FOR NYZ074-075-080-178-179.
     COASTAL FLOOD WATCH FROM LATE TONIGHT THROUGH TUESDAY MORNING
     FOR NYZ071-073-078-176-177.
NJ...BLIZZARD WARNING FROM 1 PM THIS AFTERNOON TO MIDNIGHT EST
     TUESDAY NIGHT FOR NJZ002-004-006-103>108.
     COASTAL FLOOD WATCH LATE TONIGHT FOR NJZ006-106-108.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM THIS MORNING TO 6 PM EST THIS
     EVENING FOR ANZ345.
     STORM WARNING FROM 6 PM THIS EVENING TO 6 PM EST TUESDAY FOR
     ANZ330-340-345-353-355.
     GALE WARNING FROM 6 PM THIS EVENING TO 6 PM EST TUESDAY FOR
     ANZ335-338.
     SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     ANZ350-353-355.
     GALE WARNING FROM 6 AM THIS MORNING TO 6 PM EST THIS EVENING
     FOR ANZ350-353-355.
     HURRICANE FORCE WIND WARNING FROM 6 PM THIS EVENING TO NOON
     EST TUESDAY FOR ANZ350.
-- End Changed Discussion --

&&

$$
SYNOPSIS...JC/GOODMAN/NV
NEAR TERM...MALOIT/NV
SHORT TERM...GOODMAN
LONG TERM...JC
AVIATION...BC/MALOIT
MARINE...JC/GOODMAN/MALOIT
HYDROLOGY...JC/GOODMAN
TIDES/COASTAL FLOODING...
CLIMATE...