Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 242132
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
432 PM EST MON NOV 24 2014

.SYNOPSIS...
A COLD FRONT MOVES ACROSS THE REGION TONIGHT AS LOW PRESSURE
TRACKS THROUGH SOUTHEASTERN CANADA. HIGH PRESSURE BUILDS IN
TUESDAY AND MOVES NORTHEAST TUESDAY NIGHT. LOW PRESSURE ALONG THE
SOUTHEAST COAST TUESDAY NIGHT...DEEPENS AND TRACKS
NORTHEAST...PASSING SOUTHEAST OF LONG ISLAND WEDNESDAY NIGHT...AND
THEN UP INTO THE CANADIAN MARITIMES THURSDAY. HIGH PRESSURE
GRADUALLY BUILDS IN THURSDAY NIGHT THROUGH FRIDAY AND THEN MOVES
OFFSHORE FOR THE WEEKEND. A COLD FRONT APPROACHES ON
SUNDAY...MOVING ACROSS SUNDAY NIGHT. ANOTHER HIGH FROM THE NORTH
BUILDS IN BEHIND THE FRONT FOR EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
A MOIST SOUTHERLY FLOW CONTINUES ACROSS THE AREA WITH THE FLOW
ACROSS LONG ISLAND COMING ACROSS COOLER OCEAN WATERS. DENSE FOG
REMAINS WIDESPREAD ACROSS LONG ISLAND WITH IMPROVEMENT EXPECTED
LATE THIS AFTERNOON INTO EARLY THIS EVENING AS WINDS GRADUALLY
SHIFT MORE TO THE SOUTHWEST AHEAD OF AN APPROACHING COLD FRONT.
WILL CONTINUES WITH THE DENSE FOG ADVISORY THROUGH 700 PM FOR LONG
MUCH OF LONG ISLAND.

THE COLD FRONT CROSSES THE REGION TONIGHT FROM AROUND 00Z THROUGH
08Z...AND HIGH PRESSURE BEGINS TO BUILD IN FROM THE SOUTHWEST. THE
AIR MASS IS NOT THAT COLD BEHIND THE FRONT AND WILL REMAIN ABOVE
NORMAL OVERNIGHT...IN THE UPPER 40S TO LOWER AND MID 50S.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
BROAD UPPER TROUGH REMAINS WEST OF THE AREA TUESDAY AND TUESDAY
NIGHT AS A SHORTWAVE MOVES OUT OF THE PACIFIC NORTHWEST AND INTO
THE MID SECTION OF NATION. MEANWHILE A SOUTHERN STREAM SHORTWAVE
MOVES OUT OF SOUTHERN TEXAS AND ACROSS THE GULF COAST STATES TO
THE SOUTHEAST COAST BY WEDNESDAY MORNING. AT THE SURFACE HIGH
PRESSURE BUILDS OVER THE AREA TUESDAY AND MOVES NORTHEAST TUESDAY
NIGHT. THE COMBINATION OF THE UPPER SHORTWAVES DEVELOP LOW
PRESSURE OVER THE GULF OF MEXICO AND CENTRAL PLAINS TUESDAY.
TUESDAY NIGHT THE SOUTHERN STREAM LOW MOVES OFF THE SOUTHEAST
COAST AND DEEPENS WHILE THE CENTRAL PLAINS LOW LAGS...NOT QUITE
PHASING WITH THE SOUTHERN STREAM BY WEDNESDAY MORNING.

PRECIPITATION WILL BE MOVING IN AFTER 06Z WEDNESDAY WITH ONLY
SLIGHT AND CHANCE POP UNTIL TOWARD 12Z. THE PRECIPITATION BEGINS
AS RAIN AS THE AREA WILL STILL BE WARM. AS THE LOW PUSHES NORTH
TOWARD 12Z AND PRECIPITATION BREAKS OUT INLAND...IN THE COLDER
AIR...THERE WILL BE A MIX OF RAIN AND SNOW.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
THERE IS INCREASING LIKELIHOOD OF A SIGNIFICANT WINTER STORM TO
IMPACT THE TRI-STATE AREA WEDNESDAY INTO WEDNESDAY NIGHT. THIS WOULD
HAVE MAJOR IMPACTS ON HOLIDAY TRAVEL.

MODELS REMAIN IN GOOD AGREEMENT WITH TAKING A FULL LATITUDE UPPER
TROF INTO THE EASTERN U.S. AND FORMING A COASTAL LOW ALONG THE SE
COAST TUE NIGHT. THIS LOW WILL THEN DEEPEN WHILE TRACKING NE ON WED
TO JUST EAST OF THE SOUTHERN NEW ENGLAND COAST WED NIGHT. THIS
SCENARIO WITH A MARGINALLY COLD AIRMASS AND SIGNIFICANT PCPN
INCREASES THE LIKELIHOOD FOR HEAVY WET SNOW ACROSS THE
INTERIOR...AND MIXTURE OF RAIN AND SNOW AT THE COAST WED AND WED
NIGHT. THUS...A WINTER STORM WATCH REMAINS UP FOR INTERIOR LOCATIONS
OF NE NJ...THE LOWER HUDSON VALLEY...AND CONNECTICUT. NO CHANGES
WERE MADE TO THE WATCH CONFIGURATION.

MODELS HAVE TRENDED SLIGHTLY COOLER WITH THERMO PROFILES...WITH THE
12Z GFS REMAINING THE MOST CONSISTENT IN TAKING THE DEEPENING
COASTAL LOW ACROSS THE BENCHMARK...40N...70W WED NIGHT. THE 12Z NAM
WRF IS JUST EAST...WHICH EXPLAINS THE COLDER PROFILES AND A
PRIMARILY SNOW EVENT EVEN AT THE COAST. THE 12Z ECMWF HAS TRENDED
EAST LIKE THE SREF THE LAST 24H...BUT REMAINS JUST INSIDE THE
BENCHMARK AND IS ABOUT 6H SLOWER THAN GFS AND NAM. WITH NO POLAR
HIGH TO THE NORTH...THE EVENT WILL BE STRONGLY DEPENDENT OF DYNAMICS
IN A MARGINALLY COLD AIRMASS. WET BULB TEMPS EVEN ALONG THE COAST
ARE 1 TO 2 DEG C FROM 1500 FT TO THE SFC...AND NEARLY ISOTHERMAL
ALOFT AND SLIGHTLY COOLER THAN 0 DEG C. THUS...THIS FORECAST IS
HIGHLY DEPENDENT ON STORM TRACK AND WHERE BANDING...OR STRONG
FRONTOGENETIC FORCING SETS UP. IT WILL NOT TAKE TOO MUCH TO GO FROM
ALL SNOW AND VICE VERSA...SO THIS IS WHERE THERE IS SIGNIFICANT
UNCERTAINTY IN THE FORECAST. HOWEVER...INTERIOR LOCATIONS CONFIDENCE
OF A PRIMARILY SNOW EVENT IS MUCH HIGHER THAN THE PTYPE FORECAST AT
THE COAST.

SNOWFALL AMOUNTS WILL RANGE FROM 6 TO 10 INCHES IN THE WATCH
AREA...TO AS LITTLE AS 1 TO 2 INCHES ACROSS THE EASTERN FORKS OF
LONG ISLAND. RAIN WILL CHANGE TO ALL SNOW ACROSS THE INTERIOR BY
NOONTIME...AND MIX WITH OR CHANGE TO SNOW DURING THE AFTERNOON HOURS
AT THE COAST.

AS FOR TEMPS DURING THE PERIOD...USED A BLEND OF THE NAM/GFS 2M
TEMPS/DEW POINTS. MOS IS LIKELY TOO WARM. FOR PTYPE...WITH MOST OF
THERMO PROFILE BELOW FREEZING...EXCEPT THE LOWEST 1500 FT AT THE
COAST...USED THE WET BULB IN THIS LAYER.

SNOW TAPERS OFF WED NIGHT WITH A GUSTY NW FLOW ON THE BACKSIDE OF
THE STORM. TEMPS REMAINING 5 TO 8 DEGREES BELOW NORMAL INTO
THANKSGIVING DAY WITH HIGHS AROUND 40.

STARTING AT THE UPPER LEVELS...JET STREAM SOUTH OF THE REGION
THURSDAY NIGHT THROUGH FRIDAY NIGHT WILL BE AMPLIFIED. THE JET
WILL EVENTUALLY LIFT NORTH DURING THE WEEKEND...REMAINING NEAR THE
AREA. THE JET REMAINS NEAR THE REGION AND IS PRIMARILY ZONAL FROM
THE WEEKEND INTO EARLY NEXT WEEK.

LOOKING AT THE MID LEVELS...THE TROUGH AXIS MOVES ACROSS THURSDAY
NIGHT. THE TROUGH SHIFTS EAST OF THE REGION FRIDAY AND A PRIMARY
ZONAL FLOW ESTABLISHES THEREAFTER THROUGH EARLY NEXT WEEK.

AT THE SURFACE...A HIGH PRESSURE RIDGE STARTS TO BUILD IN FROM THE
WEST THURSDAY NIGHT AND FRIDAY. THE RIDGE AXIS MOVES ACROSS FRIDAY
NIGHT AND THEN HIGH PRESSURE SLIDES OFFSHORE THIS WEEKEND. A COLD
FRONT APPROACHES SUNDAY...PUSHING THROUGH THE REGION SUNDAY NIGHT.
THIS WILL BE ASSOCIATED WITH A CLIPPER SYSTEM PASSING THROUGH
SOUTHEAST CANADA. ANOTHER HIGH PRESSURE FROM THE NORTH WILL BE
BUILDING IN NEXT MONDAY.

IN TERMS OF WEATHER...THE ONLY CHANCES FOR PRECIPITATION WILL BE
SUNDAY AND SUNDAY NIGHT IN ASSOCIATION WITH THE APPROACHING COLD
FRONT. THERE ARE LARGE UNCERTAINTIES THAT FAR OUT...SO LEFT A SLIGHT
CHANCE FOR THE WHOLE DAY SUNDAY AND ALL OF SUNDAY NIGHT. DEPENDING
ON THE TIMING...SOME PRECIP COULD BE IN THE FORM OF SNOW SHOWERS
EARLY SUNDAY OR LATE SUNDAY NIGHT...MORE SO FOR THE INTERIOR.
OTHERWISE...JUST A SLIGHT CHANCE OF RAIN SHOWERS. THE LIQUID PRECIP
TOTALS ARE CONVEYED TO BE A FEW HUNDREDTHS OF AN INCH OR LESS.

IN TERMS OF TEMPERATURES...DAYTIME HIGHS ARE FORECAST TO BE BELOW
NORMAL FRIDAY THROUGH NEXT MONDAY AND NIGHTTIME LOWS ARE FORECAST TO
BE BELOW NORMAL THURSDAY NIGHT AND FRIDAY NIGHT AND NEAR NORMAL FOR
THE NIGHTS DURING THE WEEKEND. NORMAL HIGHS LATE NOVEMBER ARE
GENERALLY IN THE UPPER 40S TO NEAR 50 WHILE NORMAL LOWS FOR THE SAME
TIME PERIOD ARE GENERALLY IN THE MID TO UPPER 30S. COLDEST DAY LOOKS
TO BE FRIDAY WITH FORECAST HIGHS ONLY IN THE LOW TO MID 30S FOR MUCH
OF THE REGION.

&&

.AVIATION /21Z MONDAY THROUGH SATURDAY/...
WARM FRONT REMAINS WELL NORTH OF THE REGION...WITH A COLD FRONT WELL
TO THE WEST. THE COLD FRONT WILL APPROACH AND MOVE ACROSS THE AREA
OVERNIGHT.

VFR CONDITIONS NOW INTO THE NYC TERMINALS AND POINTS WEST. ONLY
EXCEPTION IS JFK...HOWEVER EXPECT JFK TO GO VFR IN THE NEXT HOUR OR
SO. IT WILL TAKE ANOTHER FEW HOURS FOR EASTERN SECTIONS TO GO VFR.
EAST OF NYC...FOG HAS REDUCED VSBYS AND CIGS TO LESS THAN IFR.
EXPECTING THE FOG/STRATUS TO IMPROVE THROUGH 00Z...WITH THE
POTENTIAL FOR KGON TO HANG ON A BIT LONGER. WE SHOULD STAY MAINLY
VFR OVERNIGHT. THERE COULD BE SOME BROKEN MVFR CIGS WITH THE
PASSAGE OF THE FRONT...HOWEVER CONFIDENCE LOW FOR NOW. ONCE THE
FRONT MOVES THROUGH...EXPECT VFR CONDITIONS THROUGH THE REMAINDER
OF THE TAF PERIOD.

SOUTH WINDS GENERALLY 15 TO 20 KT WITH 25-30 KT GUSTS. STRONGEST
WINDS WILL BE ALONG THE COAST. WINDS GRADUALLY SUBSIDE THIS
EVENING...WITH SOME LOCATIONS DIMINISH TO LESS THAN 10 KT.

WINDS INCREASE ONCE AGAIN ON DURING THE DAY TUESDAY.

     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: VFR EXPECTED IN THE 21Z HOUR. CHANGES IN WIND
DIRECTION AND SPEED COULD BE OFF BY +/- 2 HOURS.

KLGA FCSTER COMMENTS: CHANGES IN WIND DIRECTION AND SPEED COULD BE
OFF BY +/- 2 HOURS. CHANCE SOME MVFR CIGS RETURN OVERNIGHT.

KEWR FCSTER COMMENTS: CHANGES IN WIND DIRECTION AND SPEED COULD BE
OFF BY +/- 2 HOURS. CHANCE SOME MVFR CIGS RETURN OVERNIGHT.

KTEB FCSTER COMMENTS: CHANGES IN WIND DIRECTION AND SPEED COULD BE
OFF BY +/- 2 HOURS. CHANCE SOME MVFR CIGS RETURN OVERNIGHT.

KHPN FCSTER COMMENTS: CHANGES IN WIND DIRECTION AND SPEED COULD BE
OFF BY +/- 2 HOURS. CHANCE SOME MVFR CIGS RETURN OVERNIGHT.

KISP FCSTER COMMENTS:  LOW FOG AND STRATUS SHOULD START TO IMPROVE
OVER THE NEXT 2 HOURS. VFR POSSIBLE BY 23Z. MVFR CIGS COULD RETURN
OVERNIGHT.

.OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...

     HIGH IMPACT EVENT WEDNESDAY INTO WEDNESDAY NIGHT...

.TUESDAY AFTERNOON...VFR. WSW WINDS 15-20 KT WITH 20-30 KT GUSTS.
.TUESDAY NIGHT...DIMINISHING WINDS. SUB-VFR CIGS POSSIBLE LATE.
.WEDNESDAY-WEDNESDAY NIGHT...MODERATE CONFIDENCE FCST. ACCUMULATING
SNOW PROBABLE FOR THE INTERIOR...BUT ACCUMULATING SNOW COULD
OCCUR CLOSER TO THE COAST DURING WED NIGHT BASED ON TRACK OF LOW.
N WINDS 10-15 KT AM...INCR 15-20 KT EVENING WITH GUSTS 25-30 KT.
.THURSDAY...BECOMING VFR. LINGERING SNOW SHOWERS POSSIBLE EARLY.
WNW 10 KT WITH GUSTS 15-20 KT.
.FRIDAY...VFR. NW 10-15 KT GUSTS UP TO AROUND 20 KT.
.SATURDAY...VFR. WEST-SOUTHWEST WINDS AROUND 10KT.

&&

.MARINE...
A STRONG AND GUSTY SOUTHERLY FLOW REMAINS ACROSS THE WATERS THIS
EVENING AHEAD OF AN APPROACHING COLD FRONT...WITH SMALL CRAFT
CONDITIONS ACROSS ALL THE FORECAST WATERS. AFTER 06Z WINDS AND
GUSTS DIMINISH AS THE COLD FRONT CROSSES THE WATERS AND WINDS
ALOFT ALSO DIMINISH. THERE WILL BE A LULL IN THE GUSTS ACROSS THE
WATERS LATE TONIGHT AND INTO TUESDAY MORNING. THEN IN THE COOLER
AIR GUSTS WILL INCREASE ON THE OCEAN WATERS TO SMALL CRAFT ONCE
AGAIN. IN ADDITION SEAS ON THE OCEAN REMAIN AT SMALL CRAFT INTO
TUESDAY EVENING...BECOMING MARGINAL DURING THE EVENING. FOR NOW
WILL HAVE A SMALL CRAFT ADVISORY ON THE OCEAN THROUGH
TUESDAY...AND ON THE REMAINDER OF THE WATERS UNTIL 06Z TONIGHT.

A COASTAL LOW BRINGS A CHANCE OF GALE CONDITIONS TO THE COASTAL
OCEAN WATERS WEDNESDAY AND WEDNESDAY NIGHT. A GALE WATCH HAS BEEN
ISSUED FOR THESE LOCATIONS. SMALL CRAFT CONDITIONS ARE LIKELY ON THE
REMAINDER OF THE WATERS DURING THIS TIME FRAME...WITH A LOW CHANCE
OF GALES.

CONDITIONS SUBSIDE TO SUB-SMALL CRAFT CONDITIONS ON THE NON-OCEAN
ZONES THURSDAY WITH LINGERING HIGH SEAS ON THE OCEAN WATERS.

SCA CONDITIONS ARE FORECAST FOR MAINLY THE OCEAN THURSDAY NIGHT
AND FRIDAY. ON FRIDAY...THIS WILL BE MAINLY FOR WINDS WITH A STEEP
ENOUGH PRESSURE GRADIENT BETWEEN THE HIGH TO THE WEST TO LOW
PRESSURE WELL INTO THE NORTH ATLANTIC. A BRIEF LULL WITH SUB SCA
CONDITIONS IS FORECAST FRIDAY NIGHT AND SATURDAY AS THE RIDGE AXIS
MOVES ACROSS AND JUST OFFSHORE. HOWEVER...THE PRESSURE GRADIENT
WILL INCREASE AS HIGH PRESSURE MOVES FARTHER OFFSHORE WITH SCA
CONDITIONS FORECAST LATE SATURDAY AFTERNOON THROUGH SUNDAY...AGAIN
MOSTLY ON THE OCEAN.

&&

.HYDROLOGY...
NO SIGNIFICANT PRECIPITATION TONIGHT THROUGH LATE TUESDAY EVENING.

THERE IS THE POTENTIAL FOR AROUND 0.75 TO 1.5 INCHES OF QPF TO FALL
FROM LATE TUESDAY NIGHT INTO EARLY THURSDAY MORNING. THE HIGHEST QPF
AMOUNTS AREA CURRENTLY EXPECTED OVER EASTERN CT/LONG ISLAND AND THE
LOWEST OVER FAR WESTERN PORTIONS OF THE TRI-STATE.

OVER THE INTERIOR MOST OF THIS WILL FALL IN THE FORM OF SNOW...SO
LITTLE IF ANY IMMEDIATE HYDROLOGIC IMPACT IS EXPECTED THERE. FARTHER
TO THE S/E...BASICALLY ALONG AND E OF I-95...THERE WILL BE A A MIX
OF RAIN AND SNOW. THIS COULD CAUSE MINOR FLOODING OF URBAN/POOR
DRAINAGE AREAS.

NO SIGNIFICANT WIDESPREAD PRECIPITATION EXPECTED THURSDAY
AFTERNOON THROUGH MONDAY.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
     MORNING FOR CTZ005>008.
NY...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
     MORNING FOR NYZ067>070.
     DENSE FOG ADVISORY UNTIL 7 PM EST THIS EVENING FOR NYZ078>081-
     176>179.
NJ...WINTER STORM WATCH FROM WEDNESDAY MORNING THROUGH THURSDAY
     MORNING FOR NJZ002-004-103-105.
MARINE...DENSE FOG ADVISORY UNTIL 7 PM EST THIS EVENING FOR ANZ330-340-
     345-350-353-355.
     SMALL CRAFT ADVISORY UNTIL 1 AM EST TUESDAY FOR ANZ330-335-338-
     340-345.
     GALE WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY EVENING
     FOR ANZ350-353-355.
     SMALL CRAFT ADVISORY UNTIL 6 PM EST TUESDAY FOR ANZ350-353-355.

&&

$$
SYNOPSIS...MET/DW
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...JM/DW
AVIATION...BC
MARINE...MET/DW/JM
HYDROLOGY...MET/DW








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