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Area Forecast Discussion
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000
FXUS61 KOKX 270137
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
837 PM EST MON JAN 26 2015

.SYNOPSIS...
A POWERFUL NOREASTER WILL IMPACT THE REGION THRU TUE. HIGH
PRESSURE BUILDS IN FOR WEDNESDAY...MOVES OVERHEAD WEDNESDAY NIGHT
AND OFFSHORE ON THURSDAY. MEANWHILE...LOW PRESSURE OVER THE
CENTRAL US TRACKS THROUGH THE GREAT LAKES THURSDAY AND ACROSS NEW
ENGLAND ON FRIDAY. HIGH PRESSURE BUILDS BACK FOR THE WEEKEND AND
THEN ANOTHER STORM SYSTEM COULD IMPACT THE AREA EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
FORECAST MAINLY ON TRACK. IMPRESSIVE LIFT VIA CLOUD TOP COOLING
OVER THE REGION AHEAD OF PIVOTING SHORTWAVE ENERGY AND COUPLED JET
STRUCTURE...WITH A SUBTROPICAL MOISTURE TAP FROM THE PACIFIC...SEEN
IN WATER VAPOR IMAGERY.

AT THE SURFACE...992 LOW PRESSURE (4 MB DEEPER IN THE LAST 3
HRS...ABOUT 200 MILES E OF THE DELMARVA...EXPECTED TO CONTINUE TO
DEEPEN AND SLOWLY TRACK NE/N TO AROUND THE 40/70 LAT/LON BENCHMARK
BY DAYBREAK. RADAR BLOSSOMING WITH BANDS OF SNOWFALL ADVECTING NW
INTO LI/CT THROUGH THE LATE EVENING...WITH SNOWFALL RATES PICKING
UP TO 1 TO 2 INCHES PER HOUR. AS LARGE BANDS SOLIDIFY
OVERNIGHT...RATES SHOULD PICK UP TO 2 TO 4 INCHES PER HOUR UNDER
THOSE BANDS...WITH SOME LOCALLY HIGHER RATES POSSIBLE WITH
CONVECTION.

SO FAR HEAVIEST SNOW TOTALS HAVE BEEN RECEIVED ACROSS NYC AND
WESTERN LI WITH EARLIER CONVERGENCE BAND DROPPING 4 TO 8 INCHES OF
SNOW.

FOR THE OVERNIGHT...STILL SOME MODEL VARIANCE ON EXACTLY HOW THE
UPPER LOW AND SURFACE REFLECTION BEHAVE LATE TONIGHT INTO TUESDAY
MORNING...WITH NAM SEEMING LIKE A WESTERN OUTLIER. THE POSITION OF
THE LOW WILL DETERMINE HOW FAR WEST BANDING WILL GET.

THE HUDSON RIVER DOWN TO NYC/NJ METRO SEEMS LIKES THE FAVORED
WESTERN BOUNDARY OF HIGH RES GUIDANCE. AT THIS TIME...WITH THE
STRENGTH AND EXPANSE OF DEEP LAYERED LIFT AND NEGATIVE TILTING OF
UPPER ENERGY...AND WCB CONVECTION TO E OF LOW...NOT READY TO MAKE
ANY WHOLESALE CHANGE TO SNOWFALL FORECAST.

SHOULD HAVE A BETTER IDEA AFTER 06Z OR SO WHERE THE WESTERN
EXTENT OF BANDING WILL DEVELOP. AND WITH THESE MILLER B TYPE
SYSTEMS...THEY TRADITIONALLY HAVE A SHARP CUTOFF IN PRECIP TO WEST
OF THE MAIN BANDING. SO AT THAT POINT WILL HAVE BETTER EVIDENCE ON
REFINING SNOWFALL AMOUNTS UNDER BAND LOCATIONS AND DECREASING SNOW
AMOUNTS TO THE WEST.

AS FOR WINDS...THEY WILL RAPIDLY INCREASE WITH GUSTS IN EXCESS OF
40-50 MPH AFTER MIDNIGHT. ACROSS EXTREME ERN LI...WIND GUSTS OF
60-70 MPH POSSIBLE.

SIGNIFICANT BLOWING AND DRIFTING OF SNOW AFT MIDNIGHT...WITH
WHITEOUT CONDITIONS.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
IT SHOULD BE A RAGING BLIZZARD AT 6AM...WITH HVY SNOW...DAMAGING
WINDS AND WHITEOUT CONDITIONS ACROSS MOST OF THE AREA. EXTREME
NWRN ZONES SUCH AS ORANGE AND WRN PASSAIC MAY BE A BIT MARGINAL
WRT WINDS.

THE LOW ESSENTIALLY STALLS SOMEWHERE S OF CAPE COD DURING THE
DAY...THEN DRIFTS AWAY TO THE NE TUE NGT BRINGING AND END TO THE
STORM. 

DEPENDING ON EXACTLY WHERE THE STORM SETS UP...THERE IS THE
POTENTIAL THAT THE DRY SLOT COULD WORK INTO THE REGION FROM THE
N...CUTTING OFF THE HEAVIER PCPN WHERE THIS OCCURS. W OF THIS AREA
WILL BE WHERE THE BEST DEFORMATION ZONE WILL BE. THE MODELS DIFFER
ON THIS...WITH THE 18Z NAM PLACING THIS BAND OVER THE CITY. 

THE SNOWFALL FCST REMAINS IN THE 20-30 INCH RANGE WITH LOCALLY
HIGHER AMTS. A LITTLE LESS FCST ACROSS NWRN ZONES...BUT THE LATEST
NAM SUGGESTS EVEN OVER 2 FT INTO ORANGE COUNTY. THE MODEL PRODUCES
2.7 INCH LIQUID OVER THE BRONX...SO THERE IS DEFINITE 3 FT
POTENTIAL WITH THIS SYS. WHERE EXACTLY THAT ULTIMATELY PLAYS OUT
REMAINS TO BE SEEN.

WRT TEMPS...THE GUIDANCE SEEMS TO BE PICKING UP THE PASSAGE OF A
CSTL FRONT ON LI. FOR EXAMPLE...THE MET BRINGS TEMPS UP TO 41
DEGREES AT KFOK TNGT. THIS SEEMS UNREALISTIC ATTM WITH SUSTAINED
30KT NLY WINDS IN THE SAME GUIDANCE. AS A RESULT...TEMPS BLW
GUIDANCE FOR THE EVENT.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
NOT MUCH CHANGE TO THE LONG TERM FORECAST AS MODEL GUIDANCE LOOKS 
SIMILAR TO PREVIOUS FORECAST.

GENERAL H5 PATTERN OF RIDGING OUT WEST AND TROUGHING OVER THE EAST 
LOOKS TO CONTINUE THROUGH THE PERIOD. VORTEX DEVELOPS OVER HUDSON 
BAY LATE THIS WEEK WITH COLD CONDITIONS PERSISTING INTO EARLY NEXT 
WEEK. ONLY TIME PERIODS OF CONCERN WITH REGARDS TO PCPN ARE THU 
NIGHT INTO FRI AS A CLIPPER SYSTEM TRACKS ACROSS THE AREA...AND 
MON...ALTHOUGH THERE IS HIGH UNCERTAINTY WITH THIS SYSTEM. THERMAL 
PROFILES ARE COLD ENOUGH FOR SNOW THU NIGHT/FRI ALTHOUGH AMOUNTS 
WILL BE LIGHT.

AS FOR MON...THE GFS IS MORE AMPLIFIED WITH THE H5 FLOW COME EARLY 
NEXT WEEK AND IS TRACKING A CLIPPER SYSTEM ACROSS THE GREAT LAKES 
WITH REDEVELOPMENT OFF THE MID ATLANTIC COAST. THE EC BEING FLATTER 
DEVELOPS A LOW OVER THE MID MISSISSIPPI VALLEY AND TRACKS IT EWD OFF 
THE MID ATLANTIC COAST AND OUT TO SEA.

HAVE GONE BELOW GUIDANCE FOR LOWS WED NIGHT DUE TO A DEEP SNOWPACK 
ON THE GROUND AND GOOD RADIATIONAL COOLING CONDS EXPECTED WITH HIGH 
PRES BUILDING OHD. WINDS WILL BE LIGHT SO WIND CHILLS WILL ONLY BE A 
FEW DEGREES BELOW AMBIENT AIR TEMPS.

TEMPS WILL GENERALLY BE IN THE 20S DURING THE DAY AND TEENS AT 
NIGHT...EXCEPT FOR WED NIGHT WHEN THEY MUCH OF THE AREA SHOULD DROP 
INTO SINGLE DIGITS AND THU/FRI WITH UPPER 20S TO LOWER 30S AND LOWER 
TO MID 30S RESPECTIVELY.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
** HIGH IMPACT SNOW AND WIND EVENT EXPECTED TONIGHT INTO 
TUESDAY NIGHT **

IFR OR LOWER CONDS DEVELOPING FOR THE NEXT FEW HOURS. 

BLIZZARD CONDITIONS EXPECTED AT KJFK/KLGA/KISP/KGON OVERNIGHT.
2-4 INCH AN HOUR RATES DEVELOP FROM SE TO NW STARTING SHORTLY AFTER 
MIDNIGHT.

WINDS BACKING TO THE NNE LATE TONIGHT...WITH GUSTS INCREASING TO 
30-40KT..LOWEST FAR W TERMINALS AND STRONGEST FAR E 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: VSBY COULD BE REDUCED TO 1/4SM AT TIMES 
THROUGH 01-02Z.

KLGA FCSTER COMMENTS: CIGS 1000-1500FT COULD PREVAIL THRU 04Z.

KEWR FCSTER COMMENTS: CIGS 1000-1500FT COULD PREVAIL THRU 04Z.

KTEB FCSTER COMMENTS: CIGS 1000-1500FT COULD PREVAIL THRU 04Z. 

KHPN FCSTER COMMENTS: CIGS 1000-1500FT COULD PREVAIL THRU 04Z. 

KISP FCSTER COMMENTS: CIGS 1000-1500FT COULD PREVAIL THRU 01-02Z.  


.OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
.TUES NIGHT...MVFR IN THE EVENING...BCMG VFR BY LATE. N-NW WINDS 
G25-35KT.
.WEDNESDAY...VFR. NW WINDS G25-30KT POSSIBLE.
.WEDNESDAY NIGHT-THURSDAY...VFR.
.THU NGT...MVFR OR LOWER CONDITIONS IN LGT SN. 
.FRI...CHC MVFR IN LGT SN IN THE AM. VFR WITH NW WNDS G25-30KT IN
THE AFTN.
.SAT...VFR.


&&

.MARINE...
970S LOW WILL PRODUCE STORM TO HURRICANE FORCE COND TNGT AND TUE.
WINDS WILL DIMINISH TO SCA LVLS TUE NGT. SEAS BUILD TO 15 TO 20 FT
ON THE OCEAN AND 4 TO 8 FT ON THE SOUND.

CONDS WILL BECOME SUB-ADVSY ON WED AS THE STORM CONTINUES TO PULL 
AWAY AND HIGH PRES BUILDS FROM THE W. THE HIGH WILL KEEP TRANQUIL 
CONDS ON THE WATERS THROUGH THU NIGHT AS THE HIGH MOVES OHD AND THEN 
OFFSHORE. SCA CONDS RETURN FRI INTO SAT AS A CLIPPER LOW INTENSIFIES 
OVER THE GULF OF MAINE AND STRONG HIGH PRES BUILDS FROM THE W.

&&

.HYDROLOGY...
LIQUID EQUIVALENT AMOUNTS OF 1.5 TO AROUND 2.25 INCHES WITH THE
BLIZZARD.

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

&&

.TIDES/COASTAL FLOODING...
A COASTAL FLOOD WARNING IS IN EFFECT FOR NORTHERN LONG ISLAND AND
WESTERN NY COAST WITHIN THE WESTERN LONG ISLAND SOUND...THE TWIN
FORKS OF LONG ISLAND...AND THE SOUTH SHORE BAYS OF LONG
ISLAND/NYC.

COASTAL FLOOD ADVISORY IS IN EFFECT FOR NYC/NJ COAST ADJACENT TO
NY HARBOR...AND THE CT COASTS.

THE NOR'EASTER IS EXPECTED TO PRODUCE MODERATE COASTAL IMPACTS FOR 
PARTS OF THE REGION OVERNIGHT INTO EARLY TUESDAY MORNING HIGH TIDE. 
THERE'S THE POTENTIAL FOR FLOODING OF VULNERABLE SHORE ROADS AND/OR 
ADJACENT PROPERTIES DUE TO HEIGHT OF STORM TIDE AND/OR WAVE ACTION.

THE MOST LIKELY SURGE FOR COASTAL AREAS IS:

- WESTERN LONG ISLAND SOUND (NY ZONES)...2 1/2 TO 3 FT ABOVE THE
ASTRONOMICAL TIDE...WITH A WORST CASE OF 3 1/2 FT.

- LONG ISLAND SOUND CT COAST...2 TO 3 FT ABOVE THE ASTRONOMICAL
TIDE...WITH A WORST CASE OF 3 1/2 FT.

- THE TWIN FORKS OF LONG ISLAND...2 1/2 TO 3 FT ABOVE THE
  ASTRONOMICAL TIDE...WITH A WORST CASE OF 3 1/2 FT.

- NEW YORK HARBOR AND THE SOUTH SHORE BAYS...2 1/2 TO 3 FT ABOVE
THE ASTRONOMICAL TIDE...WITH A WORST CASE OF 3 1/2 FT.

SIGNIFICANT BEACH EROSION AND WASHOVERS ARE EXPECTED ALONG OCEAN
FACING BARRIER BEACHES OF LONG ISLAND DUE TO STORM TIDE AND 7 TO
12 FT WAVES WEST AND 10 TO 15 FT EAST. A FEW EXPOSED WATERFRONT
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 WATERFRONT 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...
CT...BLIZZARD WARNING UNTIL MIDNIGHT EST TUESDAY NIGHT FOR 
     CTZ005>012.
     COASTAL FLOOD ADVISORY FROM 1 AM TO 7 AM EST TUESDAY FOR 
     CTZ009>012.
NY...COASTAL FLOOD WARNING FROM 1 AM TO 7 AM EST TUESDAY FOR NYZ079-
     081.
     BLIZZARD WARNING UNTIL MIDNIGHT EST TUESDAY NIGHT FOR 
     NYZ067>075-078>081-176>179.
     COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 4 AM EST 
     TUESDAY FOR NYZ072-074.
     COASTAL FLOOD WARNING FROM MIDNIGHT TONIGHT TO 6 AM EST 
     TUESDAY FOR NYZ075-080-178-179.
     COASTAL FLOOD WARNING FROM 3 AM TO 7 AM EST TUESDAY FOR NYZ071-
     073-078-176-177.
NJ...BLIZZARD WARNING UNTIL MIDNIGHT EST TUESDAY NIGHT FOR NJZ002-
     004-006-103>108.
     COASTAL FLOOD ADVISORY FROM MIDNIGHT TONIGHT TO 4 AM EST 
     TUESDAY FOR NJZ006-106-108.
MARINE...STORM WARNING UNTIL 6 PM EST TUESDAY FOR ANZ330-340-345-353-
     355.
     GALE WARNING UNTIL 6 PM EST TUESDAY FOR ANZ335-338.
     HURRICANE FORCE WIND WARNING UNTIL NOON EST TUESDAY FOR ANZ350.

&&

$$
SYNOPSIS...JMC/24
NEAR TERM...JMC/NV
SHORT TERM...JMC
LONG TERM...24
AVIATION...
MARINE...JMC/24
HYDROLOGY...JMC/24
TIDES/COASTAL FLOODING...NV
CLIMATE...






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