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Irvington On Hudson, New York, United States
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 Lat: 41.04N, Lon: 73.86W
Wx Zone: NYZ070 ICAO Used: KHPN
Area Discussion for County Warning Area OKX:
FXUS61 KOKX 021805 CCA
AFDOKX

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE NEW YORK NY
104 PM EST WED DEC 2 2009

.SYNOPSIS...
HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL MOVE FARTHER EAST
THIS AFTERNOON. THIS WILL ALLOW AN INTENSIFYING LOW PRESSURE
SYSTEM OVER THE TENNESSEE VALLEY TO TRACK NORTHEAST. THIS LOW WILL
PASS WEST OF THE REGION THURSDAY MORNING WITH A COLD FRONT MOVING
THROUGH. HIGH PRESSURE WILL RETURN LATER THURSDAY INTO FRIDAY
NIGHT. ANOTHER STORM MAY IMPACT THE AREA OVER THE WEEKEND.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CLOUDS SHOULD CONTINUE TO LOWER AND THICKEN THIS AFTERNOON...ALONG WITH
A SOUTHERLY FLOW INCREASING SLIGHTLY AS THE REST OF THE DAY
PROGRESSES. LIGHT RAINFALL MAY ENTER FAR SW PORTION OF THE CWA BY
THE EVENING RUSH HOUR...BUT THE LIKELIHOOD IS THAT RAIN BEGINS
SHORTLY AFTER THIS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
00Z MODELS...AND 06Z NAM IN DECENT AGREEMENT WITH THE DEEPENING LOW
PRESSURE SYSTEM OVER THE TENNESSEE VALLEY TO PUSH INTO THE OHIO
VALLEY/GREAT LAKES REGION OVERNIGHT...AND EVENTUALLY OVER UPSTATE
NEW YORK BY LATE THURSDAY MORNING.

RAIN CHANCES INCREASE RAPIDLY LATE THIS EVENING INTO THE FIRST
PART OF THE OVERNIGHT PERIOD...WITH CATEGORICAL POPS JUST BEFORE
MIDNIGHT.

A WARM FRONT IS EXPECTED TO PUSH ACROSS THE REGION TONIGHT...WHICH 
WILL RESULT IN A RISE IN TEMPERATURES OVERNIGHT. IN 
ADDITION...MODELS CONTINUE TO SHOW SOME ELEVATED INSTABILITY AFTER 
MIDNIGHT INTO EARLY THURSDAY MORNING...SO WILL CONTINUE TO KEEP THE 
MENTION OF ISOLATED THUNDER IN THE FORECAST. A STRONG LOW LEVEL JET 
ASSOCIATED WITH THIS SYSTEM (85 KTS!!) WILL ALSO BE IN PLACE AND
WINDS ARE EXPECTED TO MIX DOWN A BIT. WINDS ARE EXPECTED TO BE
SUSTAINED BETWEEN 25 AND 35 MPH...WITH GUSTS 50 TO 60 MPH. ANY
ORGANIZED CONVECTIONS WILL RESULT IN MUCH MORE EFFICIENT MIXING AS
WELL. WITH THESE SPEEDS RIGHT AT THE LOW END OF HIGH WIND
CRITERIA...ISSUED A HIGH WIND WATCH FROM MIDNIGHT TONIGHT THROUGH
NOON THURSDAY MORNING...BUT CONFINED IT TO ABOUT THE EASTERN TWO
THIRDS OF THE CWA...INCLUDING NYC.

IT SHOULD BE NOTED HOWEVER...THAT THE HIGHER ELEVATIONS OF THE
LOWER HUDSON VALLEY COULD SEE GUSTS 50 TO 60 MPH. WILL OBVIOUSLY
BE WATCHING THIS SITUATION CLOSELY. 

THE COLD FRONT ASSOCIATED WITH THE SYSTEM MOVES THROUGH DURING 
MORNING HOURS...SO POPS TAPER OFF IN THE MORNING FOLLOWED BY A DRY 
AFTERNOON. TOTAL RAINFALL AMOUNTS ARE EXPECTED TO AVERAGE
ANYWHERE FROM AN INCH TO AN INCH AND A HALF ACROSS THE AREA. THERE
MAY BE A FEW ISOLATED HIGHER AMOUNTS IF ANY CONVECTION OCCURS.

FOLLOWED A MAV/MET BLEND FOR HIGH HIGHS ON THURSDAY...WHICH GIVES HIGHS
IN THE 60S. HIGH TEMPS HOWEVER MAY BE A FEW DEGREES WARMER OR
COOLER DEPENDING ON THE EXACT TIMING OF THE COLD AIR ADVECTION
WITH THE COLD FRONTAL PASSAGE. TEMPS MAY FALL EARLY THURSDAY
AFTERNOON. 

HIGH PRESSURE THEN BUILDS BACK IN THROUGH THURSDAY NIGHT AND FRIDAY 
WITH DRY WEATHER.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
CONSENSUS FOR A COASTAL STORM FRIDAY NIGHT INTO SATURDAY MAINTAINS
A TRACK A BIT TOO FAR EAST...AND THE LACK OF A COLD HIGH PRESSURE
TO THE NORTH...TO HAVE A SIGNIFICANT IMPACT TO THE LOCAL AREA.
HOWEVER...WITH DEEP TROUGHING OVER THE CENTRAL US AND FAST SW FLOW
OVER THE EAST...RUN TO RUN INCONSISTENCIES ARE EXPECTED. 

BETTER MODEL AGREEMENT...FOR WHAT ITS WORTH...ON HIGH PRESSURE AND
COOL TEMPS DOMINATING SUNDAY AND MONDAY.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL DRIFT FARTHER EAST 
THIS AFTERNOON. A WARM FRONT WILL CROSS THE AREA LATE TONIGHT...FOLLOWED
BY A COLD FRONT THURSDAY MORNING AS A STRONG LOW PRESSURE CENTER
MOVES ACROSS NORTHERN NEW YORK STATE THURSDAY MORNING.

ACROSS ALL TERMINALS...ISOLATED CONVECTION AND LOW LEVEL WIND SHEAR 
POSSIBLE BETWEEN 07Z AND 12Z TONIGHT. NOT ENOUGH CONFIDENCE TO
INCLUDE IN TAFS AT THIS TIME. BETTER CHANCES OF LLWS WOULD BE OVER
KISP AND KGON...WHERE THE CORE OF THE STRONG LOW LEVEL JET WILL BE
CLOSER...BUT ALL TERMINALS COULD BE AFFECTED.

TAF COMMENTS (FORECASTER INSIGHT ON TIMING, CONFIDENCE, TRENDS AND GROUND OPS)

KEWR...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 00Z.

KEWR HOURLY WIND FORECAST
ALL WIND DIRECTIONS ARE TRUE...ADD 13 DEGREES FOR MAGNETIC    
     02/18Z 19007KT    
     02/19Z 18007KT    
     02/20Z 17008KT    
     02/21Z 15009KT    
     02/22Z 14010G16KT    
     02/23Z 13011G17KT    
     03/00Z 12012G18KT    
     03/01Z 12012G18KT    
     03/02Z 13013G19KT    
     03/03Z 13013G20KT 
     03/03Z 13013G21KT   

KJFK...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 00Z.

KLGA...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 00Z.

KTEB...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 00Z.

KHPN...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 00Z.

KSWF...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 00Z.

KISP...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 01Z.

KBDR...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 01Z.

KGON...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED THROUGH 03Z.

OUTLOOK 18Z THURSDAY THROUGH MONDAY... 
THU PM... VFR WITH GUSTY W TO NW WINDS. 
THU NIGHT-FRI...VFR WITH GUSTY W-NW WINDS. 
FRI NIGHT...VFR WITH DIMINISHING WINDS. 
SAT-SUN...CHANCE OF SUB VFR AND GUSTY N WINDS
MON: VFR.

&&

.MARINE...
WITH INCREASING CONFIDENCE IN STRONG WINDS TONIGHT...ALL WATERS
NOW HAVE BEEN UPGRADED TO A GALE WARNING. LOW END SCA GUSTS ARE
POSSIBLE ON OCEAN WATERS LATE THIS AFTERNOON...BUT ONLY IN THE
LAST FEW HOURS OF THE PERIOD. EXPECT FULL GALE BY MID TO LATE
EVENING. 

LATEST GUIDANCE SHOWS SUSTAINED 40 KTS POSSIBLE ACROSS OCEAN
WATERS SOUTH OF LONG ISLAND...AND POSSIBLE EXTREME EASTERN LI
SOUND TONIGHT. AN OCCASIONAL GUST TO STORM FORCE NOT OUT OF THE
QUESTION EITHER...ESPECIALLY IF CONVECTION DEVELOPS. SEAS BUILD UP
TO 17 FT ON THE OCEAN...AND WOULD EXPECT RATHER STEEP WAVES WITH
FAIRLY RAPID ONSET OF STRONG WINDS. 

SCA CONDITIONS WOULD LIKELY FOLLOW THROUGH AT LEAST THURSDAY 
EVENING...AND PERHAPS ALL WATERS WILL BE BELOW SCA CONDITIONS BY 
FRIDAY MORNING.

SCA CONDITIONS ARE POSSIBLE ON THE OCEAN SAT NIGHT-SUNDAY AS A
COASTAL LOW PASSES WELL SOUTH/EAST OF THE LOCAL AREA. THEN QUIET
CONDITIONS SHOULD FOLLOW FOR SUNDAY AFTERNOON AND BEYOND AS HIGH
PRESSURE TAKES CONTROL.

&&

.HYDROLOGY...
1 TO 1 1/2 INCHES OF RAIN IS EXPECTED TONIGHT INTO THURSDAY 
MORNING...BUT LOCALIZED AMOUNTS OF UP TO 2 INCHES ARE STILL 
POSSIBLE. MINOR URBANIZED FLOODING WILL BE POSSIBLE...MAINLY LATE 
WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING.

&&

.TIDES/COASTAL FLOODING...
THE APPROACH OF A FULL MOON WILL KEEP ASTRONOMICAL TIDES HIGH
OVER THE NEXT SEVERAL DAYS. AN INCREASING SOUTHERLY FLOW
ASSOCIATED WITH LOW PRES PASSING TO THE WEST...AS WELL AS WAVE
ACTION COULD CAUSE MINOR COASTAL FLOODING...MAINLY IN THE SOUTH
SHORE BACK BAYS OF LONG ISLAND THU MORNING. THE STRONGEST WINDS
LOOK TO OCCUR RIGHT AROUND THE TIME OF HIGH TIDE...BUT DUE TO THE
FAIRLY QUICK PROGRESSION OF THE STORM...WINDS WILL SHIFT TO THE SW
AND DECREASE SOME BY THE EVENING HIGH TIDE CYCLE. DEPARTURES OF
1-1.5 FT ARE NEEDED TO REACH MINOR COASTAL FLOODING LEVELS IN THE
MORNING...2-2.5 FT IN THE EVENING. MODERATE FLOODING APPEARS
UNLIKELY DUE THE SHORT DURATION OF THIS EVENT...BUT WILL STILL
KEEP A CLOSE EYE ON THE MORE VULNERABLE SOUTH SHORE BACK BAY
LOCATIONS OF NASSAU COUNTY.

HIGH SURF AND BEACH EROSION...ALONG WITH WASHOVER OF DUNES
POSSIBLE...ESPECIALLY ACROSS EASTERN LONG ISLAND WHERE RECENT
STORMS HAVE BATTERED BEACHES. 

SURGE GUIDANCE INDICATING POSSIBLE LOW WATER PROBLEMS WITH BLOW
OUT TIDES THURSDAY NIGHT INTO FRIDAY. HOWEVER...HIGH ASTRONOMICAL WATER
LEVELS SHOULD HELP EASE THINGS A BIT.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...HIGH WIND WATCH FROM MIDNIGHT EST TONIGHT THROUGH THURSDAY 
     MORNING FOR CTZ005>012.
NY...HIGH WIND WATCH FROM MIDNIGHT EST TONIGHT THROUGH THURSDAY 
     MORNING FOR NYZ071>081.
NJ...NONE.
MARINE...GALE WARNING FROM 6 PM THIS EVENING TO 1 PM EST THURSDAY FOR 
     ANZ330-335-338-340-345-350-353-355.

&&

$$

AVIATION...JC


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