Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 141749
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1249 PM EST SUN FEB 14 2016

.SYNOPSIS...
HIGH PRESSURE BUILDS OVER THE AREA THIS AFTERNOON AND OFFSHORE
TONIGHT. THE HIGH CONTINUES TO MOVE EAST AWAY INTO THE ATLANTIC
MONDAY AS A LOW PRESSURE SYSTEM DEVELOPS TO THE WEST. THIS LOW
TRAVELS NEAR OR TO THE WEST OF THE REGION TUESDAY AND INTO THE
CANADIAN MARITIMES TUESDAY NIGHT. A CLIPPER LOW MOVES IN FOR
WEDNESDAY INTO WEDNESDAY NIGHT. THEN...CANADIAN HIGH PRESSURE
RETURNS FOR THURSDAY AND FRIDAY. FOR FRIDAY NIGHT INTO SATURDAY
NEXT WEEK...ANOTHER LOW APPROACHES FROM THE NORTH AND WEST.

&&

.NEAR TERM /THROUGH TONIGHT/...
MADE MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS ON IN
OBSERVATIONS AND GUIDANCE. THE FORECAST APPEARS ON TRACK.

WIND CHILL WARNINGS/ADVISORIES HAVE BEEN ALLOWED TO EXPIRE AT
NOON WITH DECREASING WINDS MODERATING APPARENT TEMPS ABOVE -15
DEGREES...EXCEPT FOR IN A FEW ISOLATED LOCATIONS.

TEMPERATURES REMAIN SLOW TO RISE TODAY...SO HAVE LOWERED HIGHS
AROUND 2-4 DEGREES AT MOST LOCATIONS. THIS ALSO IMPACTED THE LOW
TEMPERATURES IN NYC FOR TONIGHT...WHERE TEMPERATURES ARE NOT
EXPECTED TO FALL OFF MUCH FROM THE LATE AFTERNOON HIGH.

HIGH PRESSURE MOVES ACROSS TONIGHT...WITH STRONG RADIATIONAL
COOLING CONDITIONS LIKELY FOR THE FIRST HALF OF THE NIGHT...BEFORE
HIGH CLOUDS BEGIN TO MOVE IN. THIS SHOULD ALLOW FOR TEMPS TO FALL
TO 5 TO POSSIBLY 10 BELOW ZERO ACROSS RURAL EASTERN LOCALES LIKE
THE PINE BARRENS OF LONG ISLAND AND INTERIOR VALLEYS OF CT WHERE A
SOLID SNOWPACK EXISTS. 0 TO 5 BELOW ZERO ACROSS INTERIOR VALLEYS
OF LOWER HUDSON VALLEY. ELSEWHERE TEMPS WILL LIKELY BOTTOM OUT IN
THE SINGLE DIGITS ALONG THE COASTAL PLAIN...WHILE HOLDING STEADY
IN THE MID TEENS FOR NYC METRO. TEMPS THEN COULD RISE LATE TONIGHT
AND TOWARDS DAYBREAK WITH INCREASING HIGH CLOUDS.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY/...
MODELS IN GENERAL AGREEMENT WITH SEVERAL PIECES OF PAC ENERGY
HELPING TO AMPLIFY A CENTRAL US TROUGH TODAY INTO MONDAY...WHICH
SLIDES INTO THE OHIO/TENNESSEE VALLEYS MONDAY NIGHT...AND THEN
SWINGS UP THE COAST ON TUESDAY. DETERMINISTIC MODELS AND ENSEMBLES
STILL EXHIBITING SOME MODEL SPREAD AND JUMPINESS ON TIMING AND
AMPLITUDE OF THIS SHORTWAVE ENERGY AS IT COMES UP THE COAST. SBU
SENSITIVITY TRACKING THIS MODEL SPREAD TO THE PAC ENERGY COMING
ONSHORE THIS MORNING.

THIS MODEL SPREAD IN SHORTWAVE EVOLUTION IS STILL MANIFESTING
DIFFERENCES IN TIMING AND TRACK OF LOW PRESSURE. 00Z
GFS/UKMET/CAN AND 00Z GEFS/03Z SREF ARE CLUSTERED ON A TRACK OF
LOW PRESSURE FROM THE DEEP SOUTH MONDAY MORNING...TO TENNESSEE
RIVER VALLEY MONDAY NIGHT AND THEN AN INLAND TRACK UP INTO
CENTRAL PA/NY ON TUESDAY. NAM/ECMWF TRACKS LOW PRESSURE RIGHT
ALONG THE COAST AND SLIGHTLY SLOWER. THIS IS A SIGNIFICANT
EASTWARD SHIFT FOR THE ECMWF FROM 12- 24 HRS AGO AND WESTWARD
SHIFT FOR THE GFS. AGAIN...NOT INSTILLING CONFIDENCE.

12Z GEFS/21ZSREF/12Z CMC ENSEMBLE MEANS WERE PRETTY WELL
CLUSTERED WITH A MEAN LOW TRACK ALONG THE EAST SIDE OF THE
APPALACHIANS ON TUESDAY. MUCH OF THE SPREAD WAS ON THE W/SW SIDE
OF THE LOW...WHICH MAY SIGNAL A FURTHER WEST TRACK SIMILAR TO THE
DETERMINISTIC CLUSTERING AND PERHAPS A BIT SLOWER. THIS HAS BORNE
OUT WITH THE 00Z SREF AND GEFS ENSEMBLE MEANS FURTHER WEST. BASED
ON THIS...WILL LEAN TOWARDS THE BETTER CLUSTERED LOW TRACK NEAR
THE APPALACHIANS.

IN TERMS OF SENSIBLE WEATHER...A LIKELY SCENARIO AT THIS POINT
CONTINUES TO BE LIGHT SNOW DEVELOPMENT MONDAY MORN/AFT FROM SW TO
NE FOR THE ENTIRE AREA WITH WARM ADVECTION IN DEEP SW FLOW ALOFT
OVER THE MODERATING ARCTIC AIRMASS. AS WARM AIR ADVECTION
INCREASES...EXPECTATION FOR PRECIPITATION TO CHANGE TO WINTRY MIX
AND THEN LIQUID MONDAY EVENING FROM S TO N. ALONG THE
CITY/COAST...TRANSITION FROM SNOW TO RAIN SHOULD BE FAIRLY QUICK
IN THE EVENING WITH STRENGTHENING ONSHORE FLOW. GENERALLY AN INCH
OR TWO OF SNOW ALONG THE COAST...BUT POTENTIAL FOR ROAD ICING
EXISTS A COUPLE OF HOURS AFTER TRANSITION TO RAIN AS AIR TEMPS
MAY WARM ABOVE FREEZING QUICKER THAN GROUNDS TEMPS. INCREASING
POTENTIAL FOR ICING AWAY FROM SOUTH COASTS. ACROSS INTERIOR
PORTIONS OF NE NJ...LOWER HUDSON VALLEY...AND SW CT...A GENERAL 2
TO 4 INCHES OF SNOW POSSIBLE THROUGH MON EVENING AND THEN SEVERAL
HOURS OF FREEZING RAIN POSSIBLE MONDAY NIGHT BEFORE LOW LEVEL WARM
AIR ADVECTION FINALLY SCOUR LOW- LEVEL COLD AIR MASS BY EARLY
TUESDAY MORNING. WITH PRECEDING ARCTIC AIRMASS...GROUND TEMP WARM
UP WILL LIKELY LAG AIR TEMP WARMUP...WHICH COULD RESULT IN SERIOUS
ROAD ICING ISSUES. WILL ADDRESS THREAT IN HWO.

ON TUESDAY...RAIN...POSSIBLY HEAVY AT TIMES...WITH TEMPERATURES
WELL INTO THE 40S TO 50S AS WARM CONVEYOR BELT OVERRIDES THE
REGION IF INLAND TRACK VERIFIES. A GENERAL RANGE OF 1 TO 2 1/2
INCHES OF TOTAL QPF IS FORECAST IN THE CONSENSUS OF THE MODELS.
SEE HYDRO SECTION FOR MORE INFORMATION.

CONSENSUS LOW TRACK WOULD ALSO RESULT IN WINDY CONDITIONS ALONG
THE COAST WITH 60 TO 65 KT JET AT 950 HPA MOVING OVER THE REGION.
WINDS OF 25 TO 30 MPH WITH GUSTS TO 40 MPH WOULD BE LIKELY...WITH
POTENTIAL FOR WIND ADVISORY CONDITIONS OF SUSTAINED WINDS IN THE
LOWER 30S AND GUSTS TO 50 MPH.

LOW LEVEL JET/DEEP MOISTURE AXIS MOVES EAST TUESDAY EVENING WITH
DRYING CONDITIONS.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
FOR THE REST OF THE FORECAST TUESDAY NIGHT AND
WEDNESDAY...LINGERING RAIN AND SNOW SHOWERS POSSIBLE AS MAIN LOW
MOVES INTO THE CANADIAN MARITIMES AND ANOTHER SHORTWAVE MOVES
THROUGH ALOFT WITH ITS POSITIVE VORTICITY ADVECTION. DRIER
CONDITIONS WILL BECOME MORE PREVALENT WEDNESDAY NIGHT ALTHOUGH
THERE COULD BE A FEW SNOW SHOWERS REMAINING WEDNESDAY NIGHT.
ANOTHER ROUND OF COLD AIR ADVECTION OCCURS WEDNESDAY NIGHT BEHIND
THE SHORTWAVE. STRONG CANADIAN HIGH PRESSURE MOVES IN THURSDAY
THROUGH EARLY FRIDAY WITH DRY WEATHER. ANOTHER LOW AND ANOTHER
CHANCE OF PRECIPITATION ARRIVES FRIDAY INTO SATURDAY OF NEXT WEEK.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
HIGH PRES BUILDS OVER THE REGION TNGT AND OFFSHORE ON MON AS A
WARM FRONT DEVELOPS S OF THE AREA.

DECREASING NW WINDS TODAY WITH LGT AND VRB FLOW OVERNIGHT. WINDS
BECOME E MON AHEAD OF THE WARM FRONT.

VFR THRU TNGT. LGT SNOW DEVELOPS MON MRNG...THEN BECOMES HEAVIER
AFT 18Z. MVFR OR LOWER.

.OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...
.MONDAY...SNOW DEVELOPS THRU THE DAY. RUNWAY ACCUMS POSSIBLE.
E/ESE FLOW GENERALLY AOB 10KT. MVFR OR LOWER.
.MONDAY NIGHT...IFR OR LOWER. SNOW CHANGES TO A MIX THEN RAIN AT
THE COASTS...AND TO A MIX ACROSS THE INTERIOR. SE FLOW AOB 10KT.
.TUESDAY...IFR OR LOWER WITH RAIN. SLY WINDS INCREASING TO 25-30KT
SUSTAINED. LLWS WITH 50KT BLW 1500FT.
.WEDNESDAY...MAINLY VFR. W WINDS 10-20KT.
.THU...VFR WITH NW FLOW 10-20KT.
.FRI...VFR WITH WINDS BECOMING SLY.

&&

.MARINE...
SCA COND HAVE COME TO AN END OVER THE NON-OCEAN WATERS AND THE
CSTL OCEAN WATERS W OF FIRE ISLAND INLET...SO HAVE
CANCELLED/ALLOWED TO EXPIRE ALL MARINE RELATED HEADLINES THERE.

ON THE COASTAL OCEAN WATERS E OF FIRE ISLAND INLET...STILL WILL
SEE SOME GUSTS TO 25 KT AND SEAS TO AROUND 5 FT...SO STILL HAVE
THREAT OF MODERATE FREEZING SPRAY AS WELL. LEFT HEADLINES THERE
AS IS WITH BOTH SCA AND FREEZING SPRAY ADVISORY SET TO EXPIRE IN
THOSE ZONES AT 6PM.

TRANQUIL CONDITIONS ARE EXPECTED ON ALL WATERS BY EARLY THIS
EVENING.

SUB SCA CONDITIONS MONDAY WILL BE FOLLOWED BY SCA TO GALE
CONDITIONS MONDAY NIGHT INTO TUESDAY. GALES TREND TO SCA WINDS
LATER TUESDAY AND TUESDAY NIGHT. THE WINDS TREND BELOW SCA
THEREAFTER BUT SCA OCEAN SEAS REMAIN.

&&

.HYDROLOGY...
A GENERAL 1 TO 2 1/2 INCHES OF LIQUID EQUIVALENT IS FORECAST WITH
LOCALLY HIGHER AMOUNTS MONDAY THROUGH TUESDAY NIGHT. THIS WILL BE
MOSTLY BE IN THE FORM OF RAIN.

THIS TYPE OF RAINFALL AND INITIALLY FROZEN GROUND WILL BRING
POTENTIAL FOR URBAN AND POOR DRAINAGE FLOODING. EASTERN LONG
ISLAND AND EASTERN CT ALSO HAVE MORE IN THE WAY OF SNOWPACK AND
SNOW CLOGGED DRAINAGES TO ADD TO POOR DRAINAGE FLOOD POTENTIAL.

WITH INITIALLY FROZEN GROUND...SIGNIFICANT RISES ARE LIKELY WITH
LOW POTENTIAL FOR MINOR FLOODING ALONG FLASHY SMALL STREAMS
ACROSS NE NJ/LOWER HUDSON VALLEY IF HIGH END OF RAINFALL AMOUNTS
ARE REALIZED. MMEFS AND STEVENS FAS ARE NOT SHOWING ANY AREAS
GOING INTO MINOR FLOOD AS OF YET.

&&

.TIDES/COASTAL FLOODING...
POTENTIAL EXISTS FOR MINOR COASTAL FLOOD IMPACTS WITH THE LATE
MONDAY NIGHT/EARLY TUESDAY MORNING AND POSSIBLY TUE AFT HIGH TIDE
CYCLES AHEAD OF A DEVELOPING LOW PRESSURE SYSTEM MOVING UP THE
COASTAL PLAIN. STILL QUITE A BIT OF UNCERTAINTY EXISTS ON THE
TIMING AND TRACK OF THIS SYSTEM. POSITIVE TIDAL DEPARTURES OF 2 TO
2 1/2 FT ARE NEEDED FOR MINOR FLOOD THRESHOLDS TO BE REACHED IN
THE MORNING...AND 2 1/2 TO 3 FT IN THE AFTERNOON.

&&

.CLIMATE...
WITH THE EXTREMELY COLD AIR MASS...RECORD MINIMUMS AND RECORD LOW
MAXIMUMS MAY BE REACHED. HERE ARE THE RECORDS AND FORECASTS...

STATION......RECORD LOW(YEAR)/FCST LOW BY MIDNIGHT FOR 2/13


LAGUARDIA.........8 (2016)  /  8
ISLIP.............4 (2016)  /  4

STATION......RECORD LOW(YEAR)/LOW THROUGH 8AM FOR 2/14

CENTRAL PARK.....2 (1916)  /  -1
LAGUARDIA........1 (1979)  /   1
KENNEDY..........4 (1979)  /   1
ISLIP............7 (2015)  /   0
NEWARK...........0 (1979)  /   0
BRIDGEPORT.......3 (2015*) /  -6

STATION......RECORD LOW MAXIMUM(YEAR)/FCST HIGH FOR 2/14

CENTRAL PARK....17 (1979) / 12
LAGUARDIA.......15 (1979) / 13
KENNEDY.........17 (1979) / 13
ISLIP...........26 (1987) / 11
NEWARK..........15 (1979) / 14
BRIDGEPORT......18 (1979) / 10

*IN 1979 AS WELL

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ350-
     353.
     FREEZING SPRAY ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ350-
     353.

&&

$$

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


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