Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 080017
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
717 PM EST SUN FEB 7 2016

.SYNOPSIS...
INTENSIFYING LOW PRESSURE ALONG THE SOUTHEAST U.S. COAST WILL
TRACK TO THE NORTH TONIGHT AND WILL PASS WELL SOUTH AND EAST OF
LONG ISLAND ON MONDAY. THAT LOW THEN TRACKS INTO THE CANADIAN
MARITIMES MONDAY NIGHT. AN UPPER LEVEL SYSTEM WILL THEN SPIN OVER
THE REGION THROUGH THE END OF THE WEEK. AN ARCTIC AIRMASS
OVERSPREADS THE AREA FOR THE WEEKEND.

&&

.NEAR TERM /THROUGH MONDAY/...
MINOR TWEAKS TO TEMPERATURES AND CLOUD COVER THIS EVENING.
OTHERWISE...THE FORECAST WAS ON TRACK WITH NO MAJOR CHANGES MADE.

12Z MODEL GUIDANCE ALL IN DECENT AGREEMENT...AND HAVE BROUGHT
ABOUT AN INCREASE IN PRECIPITATION ACROSS THE REGION. AS A
RESULT...TRENDED HIGHER WITH QPF AND SNOWFALL...AND HAVE GONE
AHEAD AND ISSUED WINTER STORM WARNINGS AND WINTER WEATHER
ADVISORIES FOR MUCH OF THE CWA.

HIGH PRES JUST SOUTH OF THE REGION CONTINUES TO MOVE OFFSHORE THIS
EVENING. MEANWHILE...LOW PRES CONTINUES TO INTENSIFY OFF THE
SOUTHEAST U.S. COAST...AND THAT LOW WILL PASS EAST OF CAPE
HATTERAS AFTER MIDNIGHT...AND WILL CONTINUE ON AN E-NE TRACK FROM
LATE TONIGHT THROUGH MONDAY. 1035 MB HIGH PRES BUILDS INTO EASTERN
CANADA...AND ANOTHER LOW DIVES INTO THE GREAT LAKES AND OHIO
VALLEY FROM LATE TONIGHT THROUGH MONDAY.

THE 12Z NAM/GFS/ECMWF HAVE ALL COME IN WITH THE LOW A BIT FARTHER
TO THE WEST...JUST ENOUGH TO SPREAD HEAVIER PRECIPITATION INTO
EASTERN AREAS. MODELS INDICATING HIGHER QPF AMOUNTS FOR THE
REGION...AND WITH COLDER AIR IN PLACE...EXPECTING PRECIPITATION TO
FALL AS SNOW.

THE HIGHEST QPF AMOUNTS WILL FALL OVER EASTERN LONG ISLAND AND SE
CT...WHERE 4 TO 8 INCHES OF SNOW IS POSSIBLE. WINTER STORM
WARNINGS HAVE BEEN ISSUED FOR THOSE AREAS.

ELSEWHERE...SNOW WILL BE LIGHTER OVER THE REST OF THE CWA...AND
EXPECTING A SHARP CUTOFF FROM WHERE SNOW FALLS AND WHERE IT DOES
NOT. WENT AHEAD AND HOISTED WINTER WEATHER ADVISORIES FOR THE REST
OF CT AND LONG ISLAND...AND FOR WESTCHESTER AND NYC AS WELL...AS
SNOW ACCUMULATIONS OF 2 TO 4 INCHES IS POSSIBLE IN THOSE
LOCATIONS THROUGHOUT THE PERIOD. WEST OF THAT LINE...ONLY ABOUT 1
TO 3 INCHES OF SNOW IS POSSIBLE FOR NE NJ AND THE REST OF THE
LOWER HUDSON VALLEY...SO NO HEADLINES ISSUED FOR THOSE AREAS.

WITH A TIGHT NE PRES GRADIENT DEVELOPING...CAN EXPECT STRONG WINDS
OF 15-25 MPH WITH GUSTS OCCASIONALLY AS HIGH AS 35 MPH IN THE
WARNING AREAS. NOT EXPECTING 3 HOURS OF 35 MPH WINDS AND/OR
VISIBILITIES LESS THAN 1/4 MILE...HENCE THE WINTER STORM WARNING
AS OPPOSED TO A BLIZZARD WARNING. BUT BLIZZARD-LIKE CONDITIONS POSSIBLE
IN THE WARNING AREAS. WITH A HEAVY...WET SNOW EXPECTED...DOWNED
TREES AND POWER LINES ARE POSSIBLE.

ELSEWHERE...WINDS WILL NOT BE QUITE AS STRONG...BUT GUSTS TO 30
MPH POSSIBLE FOR COASTAL AREAS.

LOWS TONIGHT WILL DROP INTO THE MID 20S TO LOW 30S. HIGHS ON
MONDAY WILL TOP OFF IN THE LOW TO MID 30S.

&&

.SHORT TERM /MONDAY NIGHT/...
SNOW TAPERS OFF MONDAY EVENING. AS LOW PRES FROM THE OHIO VALLEY
TRACKS EAST...A SECONDARY LOW LOOKS TO FORM OFF THE MID-ATLANTIC
COAST. HARD TO SAY WHERE THE HEAVIEST PRECIPITATION WILL SET
UP...BUT LIGHT SNOW IS LIKELY THROUGH THE NIGHT.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
MODELS CONTINUE TO BE IN GOOD AGREEMENT WITH RESPECT TO THE
PATTERN THROUGH THE END OF THE WEEK. CYCLONIC FLOW ALOFT PLUS LOW
LEVEL LAPSE RATES APPROACHING DRY ADIABATIC AT TIMES WILL PRODUCE
PERIODS OF LIGHT SNOW. WET BULB ZERO HEIGHTS AT OR BELOW 500FT
THROUGH THE PERIOD SO ALL SNOW IS FORECAST. BREAKS IN THE CLOUDS
WILL BE NEEDED FOR TEMPERATURES TO REACH SUPERBLEND NUMBERS...SO
DROPPED THEM DOWN A DEGREE FOR NOW. FOR SNOW
ACCUMULATIONS...MAINLY LIGHT AMOUNTS IN THE GRIDS AT THIS TIME.
HOWEVER...THERE IS THE POTENTIAL FOR TWO PERIODS OF ENHANCED
PRECIPITATION AS WEAK LOWS GET SPUN UP OFFSHORE IN THE TUE TIME
FRAME AND WED TIME FRAME. IT IS TOO FAR OUT TO PINPOINT EXACTLY
WHERE ANY HEAVIER BANDS SET UP...BUT THE POTENTIAL FOR AT LEAST A
MODERATE SNOWFALL IN THE TUE-WED PERIOD IS THERE. A FIRST WAVE OF
COLDER AIR COMES IN ON THU. VERY STEEP LOW LEVEL LAPSE RATES AGAIN
SO ANY MOISTURE IN THE AREA SHOULD BE SQUEEZED OUT WITH MORE LIGHT
SNOW. SNOW CHANCES LESSEN ON FRI AT THIS TIME WITH THE MID LEVEL
MOISTURE EXITING THE AREA. THE ARCTIC FRONT LOOKS TO BE FRI NIGHT
SETTING THE STAGE FOR A FRIGID WEEKEND. PERHAPS SOME FLURRIES OR
SNOW SHOWERS SAT...THEN DRY ON SUN WITH A 1040S HI BUILDING IN
FROM THE W.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
A WEAK COLD FRONT PUSHES SOUTH THROUGH THE AREA INTO MONDAY...AS A
STRONG COASTAL LOW TRACKS TO THE SOUTH...THEN EAST OF LONG ISLAND
INTO MONDAY EVENING.

VFR THROUGH 07Z OR SO. THEN MVFR TO IFR CONDITIONS LIKELY TO
DEVELOP IN LIGHT SNOW FROM E TO W THROUGH AROUND 13Z FOR CITY
TERMINALS...AND THEN TO IFR FROM E TO W THROUGH MIDDAY. THE
EXCEPTION IS AT KSWF...WHERE MVFR CONDITIONS ARE NOT EXPECTED
UNTIL AROUND NOON...WITH CURRENTLY NO IFR CONDITIONS FORECAST
THERE. ALSO...AT KGON/KISP...EXPECT LIFR AFTER 12Z THROUGH 19-20Z
WITH MODERATE TO HEAVY SNOW. THERE IS A LOW CHANCE FOR LIFR AT
CITY TERMINALS AND KBDR. CONDITIONS SHOULD IMPROVE TO MVFR AT CITY
TERMINALS AROUND 20Z.

WINDS INCREASE OUT OF THE NE THEN N OVERNIGHT. IT APPEARS FREQUENT
GUSTS SHOULD HOLD OFF UNTIL AROUND/JUST AFTER DAY BREAK...WITH
GUSTS OF 20-30KT LIKELY...AND PEAK GUSTS UP TO 35 KT POSSIBLE AT
COASTAL TERMINALS. EXCEPTION IS AT KSWF WHERE GUSTS TO ONLY
AROUND 15 KT ARE FORECAST. GUSTS SHOULD BEGIN TO DIMINISH
AROUND/AFTER 20Z.

LIKELY SNOWFALL ACCUMULATIONS OF:
LESS THAN 1 INCH FOR KSWF
1 TO 3 INCHES ACROSS KHPN/KEWR/KTEB
2 TO 5 INCHES FOR KLGA/KJFK/KBDR
4 TO 8 INCHES FOR KISP/KGON

.OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
.MONDAY NIGHT-THURSDAY...MVFR OR LOWER LIKELY IN INTERMITTENT SNOW.
N-NE WINDS G15-20KT POSSIBLE MONDAY NIGHT-TUESDAY NIGHT...THEN
W-NW WINDS G15-25 KT POSSIBLE WEDNESDAY-THURSDAY.
.THURSDAY NIGHT-FRIDAY...MAINLY VFR...BUT POTENTIAL FOR SCATTERED
MVFR CONDITIONS IN STRATO-CUMULUS AND FLURRIES. W-NW WINDS
G15-25KT POSSIBLE.

&&

.MARINE...
HIGH PRES OVER THE WATERS DEPARTS THIS EVENING. LOW PRES OFF THE
SOUTHEAST U.S. COAST WILL TRACK TO THE E-NE AND PASS WELL SOUTH OF
LONG ISLAND LATE TONIGHT THROUGH MONDAY.

A TIGHT PRES GRADIENT SETS UP ON THE WATERS WITH GALE FORCE WINDS
ON THE OCEAN...EASTERN LONG ISLAND SOUND...AND EASTERN LONG
ISLAND BAYS AND SMALL CRAFT ADVISORY LEVEL WINDS ON NY
HARBOR...WESTERN LONG ISLAND SOUND...AND THE SOUTH SHORE BAYS.

A FEW GUSTS TO STORM FORCE ARE POSSIBLE ON EASTERN OCEAN
WATERS...BUT CONFIDENCE NOT HIGH ENOUGH TO UPGRADE TO A WARNING.

WINDS DIMINISH FAIRLY QUICKLY MONDAY EVENING AS LOW PRES DEPARTS.
SEAS ON THE OCEAN WILL REMAIN HIGH...AS IT WILL TAKE SOME TIME FOR
THE SEAS TO SETTLE.

HEADLINES FOR THE GALE WARNINGS AND SMALL CRAFT ADVISORIES
LARGELY UNCHANGED.

SCA CONDITIONS ON THE OCEAN TUE-SAT. PERIODS OF SCA LEVEL WINDS
LIKELY IN THE TUE-SAT PERIOD ELSEWHERE.

&&

.HYDROLOGY...
LIQUID EQUIVALENT QPF WILL RANGE FROM LESS THAN A TENTH OF AN INCH
WEST OF THE HUDSON RIVER TO ALMOST AN INCH OVER SE CT AND FAR
EASTERN LONG ISLAND. THE PRECIPITATION WILL FALL AS SNOW...SO NO
HYDROLOGIC PROBLEMS ANTICIPATED. MEASURABLE PRECIPITATION IS THEN
LIKELY THROUGH AT LEAST THE MIDDLE OF NEXT WEEK. AMOUNTS APPEAR
TO BE GENERALLY LIGHT AT THIS TIME AND ALL IN THE FORM OF SNOW.

&&

.TIDES/COASTAL FLOODING...
POTENTIAL FOR MINOR TO LOCALLY MODERATE COASTAL IMPACTS MONDAY
INTO WEDNESDAY WITH A NEW MOON ON MONDAY AND A SERIES OF LOW
PRESSURES AFFECTING THE REGION.

AN INTENSE LOW PRESSURE TRACKING SE OF THE REGION MONDAY WILL
RESULT IN NE/N WINDS INCREASING TO POTENTIALLY GALE FORCE TONIGHT
AND CONTINUING INTO MONDAY. BASED ON A TRACK OF INTENSIFYING LOW
THAT SHOULD BE SE OF THE 40/70 LAT/LON BENCHMARK AND COLD AIR
DAMMING SIGNATURE...WOULD EXPECT WINDS TO BE BACKED MORE TO THE N
THAN NE. THIS SHOULD FAVOR THE LOWER SURGE GUIDANCE FOR THE MONDAY
MORNING AND NIGHT HIGH TIDE CYCLES...WHICH WILL KEEP FLOODING
MINOR AND LIMITED TO THE TYPICALLY VULNERABLE LOCALES. ISOLATED
MODERATE FLOODING POSSIBLE ALONG THE MOST VULNERABLE SHORE BAYS OF
NASSAU COUNTY. DUE TO THE LOWER ASTRONOMICAL TIDES ON MONDAY
NIGHT...WATER LEVELS SHOULD BE A BIT LOWER...WITH MINOR FLOODING
MAINLY LIMITED TO THE SOUTH SHORE BAYS OF LONG ISLAND/NY AND
ALONG THE NORTH SHORE OF LONG ISLAND ADJACENT TO WESTERN LONG
ISLAND SOUND.

AS WE HEAD INTO TUESDAYS HIGH TIDE CYCLES...WINDS SHOULD VEER
MORE TO THE NE AS ADDITIONAL WAVE/S OF LOW PRESSURE TRACK TO THE
SOUTH OF THE REGION. THE SPRING ASTRONOMICAL TIDES AND MULTI-TIDAL
CYCLE NATURE OF THE EVENT WILL FAVOR ADDITIONAL MINOR
FLOODING...WITH POTENTIAL FOR WIDESPREAD MINOR TO MODERATE
FLOODING IN THE SOUTH SHORE BAY AREAS TUESDAY. SURGE SHOULD
DECREASE HEADING INTO WEDNESDAYS HIGH TIDE CYCLE...BUT LINGERING
MINOR COASTAL FLOODING IS STILL POSSIBLE...PARTICULARLY INT HE
SOUTH SHORE BAYS AREAS.

HIGH SURF OF 6 TO 10 FT WILL ONCE AGAIN PRESENT A MODERATE TO
HIGH THREAT FOR AREAS OF DUNE TOE EROSION ALONG THE ATLANTIC OCEAN
BEACHES...AND A LOCALIZED POTENTIAL FOR OVERWASHES ON FIRE
ISLAND. THIS IS BASED ON MODELED IMPACTS OF GALE CENTER FROM THE
USGS COASTAL CHANGE HAZARDS PORTAL.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WARNING FROM 3 AM TO 6 PM EST MONDAY FOR CTZ007-
     008-011-012.
     WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM EST MONDAY FOR
     CTZ005-006-009-010.
     COASTAL FLOOD ADVISORY FROM 10 AM TO 1 PM EST MONDAY FOR
     CTZ009-010.
NY...WINTER STORM WARNING FROM 3 AM TO 6 PM EST MONDAY FOR
     NYZ078>081.
     COASTAL FLOOD ADVISORY FROM 7 AM TO 11 AM EST MONDAY FOR
     NYZ074-075-080-081-178-179.
     WINTER WEATHER ADVISORY FROM 3 AM TO 6 PM EST MONDAY FOR
     NYZ070>075-176>179.
     COASTAL FLOOD ADVISORY FROM 10 AM TO 1 PM EST MONDAY FOR
     NYZ071-073-078-177.
     HIGH SURF ADVISORY FROM 1 AM MONDAY TO 7 AM EST TUESDAY FOR
     NYZ080-081-178-179.
     COASTAL FLOOD ADVISORY FROM 7 PM TO 11 PM EST MONDAY FOR
     NYZ075-080-178-179.
     COASTAL FLOOD ADVISORY FROM 10 PM MONDAY TO 1 AM EST TUESDAY
     FOR NYZ078-177.
NJ...COASTAL FLOOD ADVISORY FROM 7 AM TO 11 AM EST MONDAY FOR
     NJZ006-106-108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ335-338-345.
     GALE WARNING UNTIL 6 PM EST MONDAY FOR ANZ330-340-350-353-355.

&&

$$

SYNOPSIS...JMC/MPS
NEAR TERM...JMC/MPS
SHORT TERM...MPS
LONG TERM...JMC
AVIATION...MALOIT
MARINE...JMC/MPS
HYDROLOGY...JMC/MPS
TIDES/COASTAL FLOODING...NV


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