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

.SYNOPSIS...
HIGH PRESSURE SLOWLY RETREATS TO THE EAST INTO MONDAY NIGHT.
MEANWHILE...AN AREA OF LOW PRESSURE MOVES ACROSS THE DEEP SOUTH
THROUGH MONDAY...THEN TRACKS NORTHEAST INTO UPSTATE NEW YORK BY
TUESDAY EVENING. LOW PRESSURE MOVES INTO THE CANADIAN MARITIMES
TUESDAY NIGHT INTO WEDNESDAY. AN ASSOCIATED COLD FRONT MOVES
ACROSS LATE TUESDAY NIGHT. A SECONDARY COLD FRONT APPROACHES
WEDNESDAY AND MOVES ACROSS WEDNESDAY NIGHT. HIGH PRESSURE BUILDS
FOR THURSDAY THROUGH FRIDAY. ANOTHER FRONTAL SYSTEM MOVES TO THE
NORTH OF THE REGION FRIDAY NIGHT THROUGH SATURDAY NIGHT. WEAK HIGH
PRESSURE FOLLOWS FOR NEXT SUNDAY.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
NORTHERN STREAM RIDGING CROSSES THE AREA TONIGHT...WITH A WEAK
700-500 HPA SHORTWAVE APPROACHING LATE TONIGHT. THIS SHORTWAVE
WILL BRING AN INCREASE IN CLOUD COVER ONCE THE RIDGE AXIS PASSES
TO THE EAST AFTER MIDNIGHT.

WITH A MAINLY CLEAR SKY THROUGH MOST OF THE NIGHT...AND WINDS
BECOMING LIGHT AND VARIABLE...IF NOT CALM...SHOULD HAVE DECENT
RADIATIONAL COOLING.

LOWS TONIGHT ARE A BLEND OF MAV/MET/ECS GUIDANCE WITH NAM AND GFS
2-METER TEMPERATURES...WEIGHED TOWARDS THE LOWEST GIVEN VALUE AT
ANY GIVEN POINT...TO REFLECT THAT GUIDANCE OFTEN UNDER DOES THE
EXTENT OF RADIATIONAL COOLING. LOWS SHOULD BE AROUND 20 DEGREES
BELOW NORMAL.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
CONSENSUS IS GROWING THAT THE SURFACE LOW ASSOCIATED WITH A
700-500 HPA TROUGH THAT WILL TRACK FROM THE PLAINS TO THE WESTERN
APPALACHIANS BY TUESDAY MORNING...THEN LIFT NORTHEAST ON
TUESDAY...WILL TRACK TO THE WEST...THEN NNW OF THE CWA. GIVEN THIS
CONFIDENCE HAS INCREASED THAT THE AREA WILL SEE A PERIOD OF SNOW
DEVELOPING LATE MONDAY MORNING/MONDAY AFTERNOON...AND THAT THIS
SNOW WILL MIX WITH/CHANGE TO FREEZING RAIN...THEN RAIN MONDAY
NIGHT/EARLY TUESDAY MORNING...WITH THE POSSIBLE EXCEPTION OF THE
TWIN FORKS OF LONG ISLAND...WHERE THE TRANSITION COULD BE
DIRECTLY TO RAIN.

CURRENTLY FORECASTING 2-5 INCHES OF SNOW...FOLLOWED BY UP TO A
TENTH OF AN INCH OF ICE FOR INTERIOR S CT/LOWER HUDSON VALLEY AND
W PASSAIC AND BERGEN COUNTIES. A GLAZE OF ICE...ALONG WITH UP TO
4 INCHES OF SNOW (HIGHEST TOTALS W OF GARDEN STATE PARKWAY) FOR
COASTAL S CT...MOST OF NE NJ...AND NASSAU/S WESTCHESTER AND W
SUFFOLK COUNTIES. EXPECT THE TRANSITION TO RAIN TO BE DONE BY
AROUND MIDNIGHT IN THIS SOUTHERN GROUP. EXPECT UP TO 1" OF SNOW
OVER E SUFFOLK...WITH A QUICK TRANSITION TO RAIN MONDAY EVENING. AS
A RESULT...HAVE ISSUED WINTER WEATHER ADVISORIES FROM 1PM MONDAY-
7AM TUESDAY FOR THE NORTHERN TIER...1 PM MONDAY- MIDNIGHT TUESDAY
FOR THE SOUTHERN TIER GROUPING...WITH NO HEADLINES FOR E SUFFOLK.

LOCALLY HEAVY RAINFALL IS THEN POSSIBLE ON TUESDAY. REFER TO THE
HYDROLOGY SECTION OF THE AFD FOR POSSIBLE AMOUNTS AND IMPACTS.
ALSO WITH A 55-70 KT 950-850 HPA JET...THERE IS THE POTENTIAL FOR
GUSTY WINDS...DEPENDING ON HOW DEEP INTO THE WARM SECTOR THE AREA
GETS. GUSTS NEAR THE COASTS/HIGHER ELEVATIONS COULD BE IN THE
30-40MPH RANGE...WITH 20-30 MPH GUSTS ELSEWHERE. THERE IS STILL
SOME UNCERTAINTY ON EXACTLY HOW GUSTY THE WINDS WILL BE...AS THE
LOW LEVEL JET WILL BE WORKING AGAINST A LIKELY LOW LEVEL
INVERSION.

EVEN THOUGH CONFIDENCE IS HIGH ENOUGH TO ISSUE A WINTER WEATHER
ADVISORY...THERE IS STILL SOME UNCERTAINTY ON THE STORMS EXACT
TRACK...STRENGTH AND TIMING.

FOR HIGHS ON MONDAY USED A BLEND OF NAM AND GFS 2-METER
TEMPERATURES WITH MAV/MET/ECS GUIDANCE AND A MIX DOWN FROM 975 HPA
PER BUFKIT SOUNDINGS. THIS WAS WEIGHED TOWARDS THE LOWEST VALUE AT
ANY GIVEN GRIDPOINT TO REFLECT THE IMPACT OF COLD AIR
DAMMING...WHICH IS OFTEN UNDER DONE IN GUIDANCE. HIGHS SHOULD BE
AROUND 5-10 DEGREES ABOVE NORMAL.

LOWS MONDAY NIGHT SHOULD OCCUR IN THE EVENING...THEN SLOWLY RISE
THROUGH THE NIGHT IN RESPONSE TO STRONG LOW LEVEL WARM ADVECTION.
LOWS WILL BE NEAR THE HIGHS FOR MONDAY...WITH AN AROUND 10 DEGREE
TEMPERATURE RISE FORECAST THROUGH THE NIGHT.

HIGHS ON TUESDAY WILL DEPEND ON HOW FAR N A COASTAL FRONT PUSHES
INTO THE AREA. GIVEN THE STRENGTH OF THE LOW LEVEL JET...GUIDANCE
OFTEN UNDER DOES HOW FAR N IT GETS IN SITUATIONS LIKE THESE. AS A
RESULT...DID BLEND IN A MIX DOWN FROM 975 HPA ALONG WITH NAM AND
GFS 2-METER TEMPERATURES AND A BLEND OF MAV/MET/ECS GUIDANCE.
HIGHS SHOULD BE 10-15 DEGREES AND POSSIBLY UP TO 20 DEGREES ABOVE
NORMAL...ONCE AGAIN DEPENDING ON THE COASTAL FRONT.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
LINGERING SHOWERS TUESDAY EVENING AHEAD OF THE COLD FRONT WILL TAPER
OFF LATE WEST TO EAST. THERE WILL BE ANOTHER SHORTWAVE APPROACHING
THOUGH AS ANOTHER COLD FRONT AT THE SURFACE APPROACHES. A BRIEF DRY
GAP LATE TUESDAY NIGHT WILL BE FOLLOWED BY ANOTHER CHANCE OF SHOWERS
WEDNESDAY INTO WEDNESDAY NIGHT. THE POPS ARE ONLY SLIGHT CHANCE
WEDNESDAY NIGHT. WEDNESDAY...PRECIPITATION N/W OF NYC MAINLY SNOW
SHOWERS WHILE ACROSS NYC AND COAST...THEY ARE RAIN SHOWERS.
WEDNESDAY...PRECIPITATION WILL BE MOSTLY SNOW SHOWERS.

DRY WEATHER THURSDAY THROUGH FRIDAY WITH STRONG CANADIAN HIGH
PRESSURE BUILDING IN.  ANOTHER LOW PRESSURE AREA MOVES NORTHWEST OF
THE REGION FRIDAY NIGHT THROUGH SATURDAY NIGHT WITH RAIN AND SNOW
SHOWERS. THE POPS ARE ONLY AT MOST 30 PERCENT DUE TO MODEL
DISAGREEMENT WITH TIMING. A WARM FRONT MOVES ACROSS FRIDAY NIGHT
INTO SATURDAY WITH A COLD FRONT MOVING ACROSS LATE SATURDAY. WEAK
HIGH PRESSURE FOLLOWS BEHIND THAT FOR NEXT SUNDAY WITH DRY WEATHER
RETURNING.

REGARDING TEMPERATURES...THEY WILL BE ABOVE NORMAL TUESDAY NIGHT AND
WEDNESDAY...TRENDING CLOSER TO NORMAL WEDNESDAY NIGHT THROUGH
FRIDAY. THEY TREND ABOVE NORMAL ONCE AGAIN FRIDAY NIGHT INTO NEXT
WEEKEND.

&&

.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
HIGH PRES BUILDS OVER THE REGION TONIGHT AND OFFSHORE ON MON AS A
WARM FRONT DEVELOPS S OF THE AREA.

NW WINDS CONTINUE TO DECREASE THIS EVE WITH LIGHT AND VRB FLOW
OVERNIGHT. WINDS BECOME E MON AHEAD OF THE WARM FRONT.

VFR THRU TONIGHT. LIGHT SNOW DEVELOPS MON MORNING...THEN BECOMES
HEAVIER AFT 18Z. MVFR OR LOWER WITH THE SNOW.

.OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...
.MONDAY...SNOW DEVELOPS THRU THE DAY. RUNWAY ACCUMULATIONS POSSIBLE.
E/ESE FLOW GENERALLY AT OR BELOW 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 AT OR BELOW 10KT.
.TUESDAY...IFR OR LOWER WITH RAIN. SLY WINDS INCREASING TO 25-30KT
SUSTAINED. LLWS WITH 50KT BELOW 1500FT. 
.WEDNESDAY...MAINLY VFR. W WINDS 10-20KT.
.THU...VFR WITH NW FLOW 10-20KT.
.FRI...VFR WITH WINDS BECOMING SLY.

&&

.MARINE...
GUSTS TO 25 KT WERE PERSISTING AT 44017...SO LEFT UP THE SCA E OF
MORICHES INLET UNTIL 6 PM. HOWEVER GIVEN THE WARMER WATER
THERE...CURRENTLY REPORTING ONLY LIGHT ICING AT 44017...SO
CANCELED THE FREEZING SPRAY ADVISORY THERE. 

THE PRESSURE GRADIENT BECOMES SLACK OVER THE WATERS TONIGHT...WITH
WINDS 10 KT OR LESS THROUGHOUT. TRANQUIL CONDITIONS CONTINUE
MONDAY MORNING...THEN WINDS INCREASE OVER THE COASTAL OCEAN WATERS
MONDAY AFTERNOON...BUT REMAIN BELOW SCA LEVELS.

THERE IS THE POSSIBILITY THAT GUSTS OF 25-30KT ARE POSSIBLE ON THE
COASTAL OCEAN WATERS AND E SOUND/BAYS...WITH SMALL CRAFT OR GALE
GUSTS POSSIBLE ON ALL WATERS ON TUESDAY. WILL HIGHLIGHT THE THREAT
FOR GALE GUSTS IN THE HWO.

POSSIBLE LINGERING GALES ON THE OCEAN TUESDAY EVENING
WITH OTHERWISE LINGERING SCA CONDITIONS. THE SCA CONDITIONS DROP OFF
FOR NON-OCEAN WATERS LATE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT
WHILE REMAINING AT SCA LEVELS FOR THE OCEAN. FOR
THURSDAY...WIDESPREAD SCA IS POSSIBLE. THURSDAY NIGHT AND
FRIDAY...CONDITIONS TREND TO BELOW SCA WITH HIGH PRESSURE MOVING IN.

&&

.HYDROLOGY...
DRY THROUGH THE MORNING RUSH ON MONDAY MORNING. THEN FROM 1 TO 1
3/4 INCHES OF LIQUID EQUIVALENT IS FORECAST FROM MONDAY AFTERNOON
INTO TUESDAY EVENING...WITH LOCALLY HEAVIER AMOUNTS POSSIBLE.
ALSO...THERE IS SOME UNCERTAINTY ON AMOUNTS DUE TO STILL SOME
QUESTIONS ON EXACT STORM TRACK AND STRENGTH.

EVEN WITH SOME OF THIS INITIALLY GOING TO SNOW AND FREEZING
RAIN...GIVEN THE AMOUNT OF WARMING EXPECTED ON TUESDAY...EXPECT
ALMOST ALL OF THIS TO END UP BEING REALIZED AS LIQUID WATER
EVENTUALLY...EXCEPT FOR MAYBE AT THE HIGHER ELEVATIONS N/W OF NYC
WHERE SOME SNOW COULD LINGER. AS RESULT...THE MOST LIKELY IMPACT
IS FOR URBAN AND POOR DRAINAGE FLOODING.

HOWEVER...WITH THE GROUND INITIALLY FROZEN...SIGNIFICANT RISES
ARE LIKELY WITH LOW POTENTIAL FOR MINOR FLOODING ALONG FLASHY
SMALL STREAMS ACROSS NE NJ/LOWER HUDSON VALLEY FOR AREAS
EXPERIENCING LOCALLY HIGHER AMOUNTS. WHILE THIS POTENTIAL IS
LOW...THIS THREAT WILL BE HIGHLIGHTED IN THE HWO.

TUESDAY NIGHT...ONLY POSSIBLE CONCERNS ARE FOR ANY RIVERS
AND STREAMS THAT MAY BE SLOW TO SUBSIDE DUE TO RESIDUAL RUNOFF.
RESIDUAL MINOR FLOODING IS POSSIBLE. OTHERWISE...NO SIGNIFICANT
WIDESPREAD RAIN IS EXPECTED WITH NO OTHER ISSUES ANTICIPATED.

&&

.TIDES/COASTAL FLOODING...
POTENTIAL EXISTS FOR MINOR COASTAL FLOOD IMPACTS WITH THE TUESDAY
AFTERNOON HIGH TIDE CYCLE DUE TO STRONG SE FLOW. FOR NOW IT
APPEARS THE WINDS WILL INCREASE AND BACK TO THE SE TOO LATE TO
BRING COASTAL FLOODING CONCERNS DURING THE LATE MONDAY
NIGHT/EARLY TUESDAY MORNING HIGH TIDE CYCLE.

THERE STILL EXISTS QUITE A BIT OF UNCERTAINTY EXISTS ON THE
TIMING AND TRACK OF THIS SYSTEM. POSITIVE TIDAL DEPARTURES OF 2
1/2 TO 3 FT ARE NEEDED TO REACH MINOR COASTAL FLOOD BENCHMARKS
TUESDAY AFTERNOON...WITH BEST CHANCES IN THE BACK SHORE BAYS ALONG
THE S COAST OF NYC/W LONG ISLAND...W PORTIONS OF THE LONG ISLAND
SOUND...AND STATEN ISLAND GIVEN THE SE FLOW.

&&

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

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

CENTRAL PARK....17 (1979) / 15
LAGUARDIA.......15 (1979) / 16
KENNEDY.........17 (1979) / 17
ISLIP...........26 (1987) / 13
NEWARK..........15 (1979) / 17
BRIDGEPORT......18 (1979) / 13

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY 
     FOR CTZ005>008.
     WINTER WEATHER ADVISORY FROM 1 PM MONDAY TO MIDNIGHT EST 
     MONDAY NIGHT FOR CTZ009>012.
NY...WINTER WEATHER ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY 
     FOR NYZ067>070.
     WINTER WEATHER ADVISORY FROM 1 PM MONDAY TO MIDNIGHT EST 
     MONDAY NIGHT FOR NYZ071>075-078-080-176>179.
NJ...WINTER WEATHER ADVISORY FROM 1 PM MONDAY TO 7 AM EST TUESDAY 
     FOR NJZ002-103.
     WINTER WEATHER ADVISORY FROM 1 PM MONDAY TO MIDNIGHT EST 
     MONDAY NIGHT FOR NJZ004-006-104>108.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ350-
     353.

&&

$$

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

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