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West Nyack, New York, United States (10994)
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 Lat: 41.09N, Lon: 73.97W
Wx Zone: NYZ069 ICAO Used: KHPN
Area Discussion for County Warning Area OKX:
FXUS61 KOKX 271738
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1238 PM EST FRI NOV 27 2009

.SYNOPSIS...
LOW PRESSURE EAST OF THE AREA WILL CONTINUE TO RAPIDLY DEEPEN AND
MOVE TO THE GULF OF MAINE BY TONIGHT. THE LOW WILL CONTINUE TO
MOVE SLOWLY NORTH INTO SATURDAY AS HIGH PRESSURE BUILDS OVER THE
SOUTHEAST. THE HIGH WILL MOVE OFF THE COAST ON SUNDAY...FOLLOWED
BY AN APPROACHING COLD FRONT SUNDAY NIGHT AND MONDAY. HIGH
PRESSURE WILL BUILD OVER THE AREA TUESDAY AND WEDNESDAY. ANOTHER
STORM WILL MOVE INTO THE MID ATLANTIC REGION ON THURSDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BACK EDGE OF RAIN ORIENTED N-S FROM FAIRFIELD COUNTY IN SOUTHERN
CT TO WESTERN SUFFOLK ON LONG ISLAND LATE THIS MORNING. EXPECT A
SLOW PROGRESSION OF THE BACK EDGE TO THE EAST THIS AFTERNOON...
HOWEVER...A STRENGTHENING NW FLOW WILL ALLOW FOR DRYING AS THE
AFTERNOON PROGRESSES WITH THE BAND GRADUALLY BREAKING UP. THE
HIGHEST CHANCES FOR RAINS WILL BE ACROSS EASTERN LI AND SE CT THIS
AFT. STILL THOUGH...WITH THE UPPER TROF PIVOTING THROUGH THE ENTIRE
FORECAST AREA...FELT IT WOULD BE PRUDENT TO KEEP LOW CHC POPS TO
THE WEST OF THE MAIN AREA OF RAIN.

TEMPS WILL FLUCTUATE LITTLE THE NEXT SEVERAL HOURS WITH HIGHS IN
THE MID TO UPPER 40S INLAND AND AROUND 50 ALONG THE COAST. THESE
ARE SEASONABLE.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AS THE LOW RAPIDLY DEEPENS OFF THE ME COAST LATE TONIGHT/EARLY 
SATURDAY...EXPECT WINDS TO INCREASE CLOSE TO WIND ADVISORY CRITERIA. 
STRONGEST WINDS EXPECTED TO BE LATE TONIGHT INTO SAT MORNING AS 
WINDS INCREASE ALL THE WAY UP THE COLUMN. WE HAVE SEEN BEST MOMENTUM 
TRANSFER OCCUR WHEN WINDS INTENSIFY ABOVE THE MIXED LAYER. FOR NOW 
THOUGH...WILL BEGIN WIND ADVISORY TONIGHT...AND RUN IT THROUGH NOON 
SATURDAY.

AS BOTH THE UPPER LEVEL AND SURFACE LOWS EXIT THE AREA TOWARDS THE 
CANADIAN MARITIMES...RAIN CHANCES WILL DIMINISH FROM WEST TO EAST 
THROUGHOUT THE DAY SATURDAY.  IN ADDITION...WESTERLY WINDS WILL 
BEGIN TO DECREASE AS THE HEIGHT AND PRESSURE GRADIENTS BEGIN TO 
RELAX.  COLDER AIR WILL ADVECT OVER THE AREA THROUGHOUT THE DAY 
SATURDAY...HOWEVER...EXPECT PRECIP TO HAVE ALREADY MOVED OUT OF THE 
AREA FOR ANY WIDESPREAD SNOW.  THAT SAID...HIGHER ELEVATIONS COULD DROP 
QUICK ENOUGH TO SEE A STRAY FLAKE MIXED IN BEFORE THE SHOWERS 
COMPLETELY EXIT THE AREA.  EXPECT OVERNIGHT LOWS TO REMAIN NEAR OR 
SLIGHTLY ABOVE CLIMATE NORMALS AS CLOUD COVER REMAINS ENTRENCHED 
OVER THE AREA PRECLUDING ANY RADIATIONAL COOLING. HOWEVER...HIGHS ON 
SATURDAY WILL BE SLIGHTLY BELOW SEASONAL AVERAGES AS THE COOLER AIR 
FILTERS OVER THE AREA BEHIND THE EXITING SYSTEMS.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
WEAK RIDGING WILL MOVE OVER THE AREA ON SUNDAY LEAVING THE AREA 
PRECIP FREE BEFORE THE NEXT SYSTEM ARRIVES FROM THE WEST.  EXPECT 
SKIES TO BE SUNNY WITH AFTERNOON HIGHS CLOSE TO OR SLIGHTLY ABOVE 
SEASONAL NORMS.  

PRECIPITATION CHANCES WILL BEGIN TO INCREASE AGAIN SUNDAY NIGHT INTO 
MONDAY MORNING AS AN UPPER LEVEL TROUGH SWINGS THROUGH THE CENTRAL 
CONUS WITH AN ASSOCIATED SURFACE FRONT.  EXPECT THE FRONT TO SWING 
THROUGH MON/MON NITE TIME FRAME. WHILE MODELS ARE NOT IN COMPLETE 
AGREEMENT ON TIMING OF THE FRONT...EXPECT IT TO HAVE CLEARED THE 
AREA BY TUESDAY WITH RIDGING MOVING BACK OVER THE AREA. TEMPERATURES 
WILL REMAIN CLOSE TO SEASONAL THROUGH MID WEEK.

PATTERN CONTINUES TO GET COMPLICATED AS NORTHERN AND SOUTHERN STREAM 
SYSTEMS BEGIN TO TAKE AIM ON THE AREA.  HOWEVER...THE SOLUTIONS 
APPEAR TO BE SIGNIFICANTLY DIFFERENT/OUT OF AGREEMENT FROM WHAT THEY 
WERE JUST 24 HOURS AGO...SO WILL WAIT FOR BETTER RESOLUTION BEFORE 
TACKLING THE EXTENDED ATTM.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
LOW PRES SOUTH OF NANTUCKET WILL DEEPEN THE REMAINDER OF THIS 
AFTERNOON AS IT TRACKS NORTH INTO THE GULF OF MAINE BY TONIGHT. 

IMPROVEMENT IS EXPECTED TO VFR OVER THE NEXT FEW HOURS FROM W TO E. 
BACK EDGE OF PRECIPITATION IS MOVING EASTBOUND MORE QUICKLY AND WILL 
EXIT THE AREA BY LATER THIS AFTERNOON. WILL REMOVE -RA FOR ALL AREAS 
EXCEPT FOR KGON.  CAN'T RULE OUT AN INSTABILITY SHOWER OVER WESTERN 
AREAS BUT CONFIDENCE NOT HIGH ENOUGH TO INCLUDE IN TERMINALS.  

WINDS WILL BE BIGGEST IMPACT TO AREA TERMINALS LATER TODAY AS LOW 
STRENGTHENS AND MOVES NORTH OF THE AREA.  AT KEWR...EXPECT WINDS TO 
SHIFT PRIMARILY LEFT OF 310 BY 20Z.  GUSTS WILL INCREASE TO NEAR 
25KTS THIS AFTERNOON AND LIKELY GUST OVER 30 KTS AFTER 00Z. 
OVERNIGHT...WINDS COULD GUST NEAR 40KT BRIEFLY AT A FEW LOCATIONS. 
GUSTY WINDS WILL CONTINUE INTO SATURDAY. WIND FORECAST CONFIDENCE IS 
HIGH.
 

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

KEWR...WINDS MAY STAY RIGHT OF OR ON 310 UNTIL 22Z-00Z. 

KEWR HOURLY WIND FORECAST
ALL WIND DIRECTIONS ARE TRUE...ADD 13 DEGREES FOR MAGNETIC
     27/16Z 32015G22KT 
     27/17Z 31017G24KT 
     27/18Z 31018G25KT 
     27/19Z 31018G25KT 
     27/20Z 31019G26KT 
     27/21Z 31019G26KT 
     27/22Z 30019G30KT 
     27/23Z 30019G30KT 
     28/00Z 30018G29KT 
     28/01Z 30018G29KT 
     28/02Z 30018G29KT 
     28/03Z 29018G29KT 

KJFK...SLOW IMPROVEMENT TO VFR BY 18Z.  

KLGA...SLOW IMPROVEMENT TO VFR BY 18Z.

KTEB...IMPROVEMENT TO VFR MAY DELAYED +1/-1 AN HOUR.  

KHPN...IMPROVEMENT TO VFR MAY DELAYED +1/-1 AN HOUR. 

KSWF...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS 
ANTICIPATED.

KISP...IMPROVEMENT TO VFR MAY DELAYED +1/-1 AN HOUR.

KBDR...IMPROVEMENT TO VFR MAY DELAYED +1/-1 AN HOUR.

KGON...IMPROVEMENT TO VFR MAY DELAYED +1/-1 AN HOUR. 

OUTLOOK 12Z SATURDAY THROUGH TUESDAY... 
SAT-SAT NIGHT...VFR. STRONG GUSTY W/NW WINDS. 
SUN...VFR. DIMINISHING WINDS. 
SUN NIGHT-MON NIGHT...SUB-VFR POSSIBLE. 
TUE...VFR.

&&

.MARINE...
LOW PRESSURE RAPIDLY INTENSIFIES AS IT MOVES JUST EAST OF THE
WATERS. NORTH/NORTHWEST WINDS INCREASE THROUGH THE AFTERNOON.
GALES LIKELY BY LATE DAY...WITH SMALL CRAFT ADVISORY WINDS
ANTICIPATED FOR MUCH OF THE NEAR TERM.

GALES CONTINUE TONIGHT AND SATURDAY AS THE LOW DEEPENS JUST OFF THE 
MAINE COAST. COULD SEE A FEW GUSTS TO 50 KTS (STORM FORCE) LATE 
TONIGHT/EARLY SATURDAY MORNING...BUT FEEL THESE WINDS WILL BE FEW 
AND FAR BETWEEN. AS SUCH...GALE WARNING REMAINS.

WINDS DIMINISH SATURDAY NIGHT AS PRESSURE GRADIENT WEAKENS. WINDS 
BACK TO THE WEST AS HIGH PRESSURE PASSES TO THE SOUTH. WINDS 
INCREASE AHEAD OF A COLD FRONT SUNDAY NIGHT...THEN TURN TO THE 
NORTHWEST MONDAY AND TUESDAY.

SEAS BUILD TODAY AND TONIGHT...AND EXPECT ROUGH CONDITIONS IN STRONG 
WEST/NORTHWEST FLOW ALL WATERS. WESTERLY FETCH WILL RESULT IN MUCH 
HIGHER SEAS ACROSS THE EASTERN WATERS. SEAS SUBSIDE SLOWLY SATURDAY 
NIGHT AND WILL FOLLOW WAVE WATCH III OUTPUT CLOSELY THROUGH EARLY 
NEXT WEEK.

&&

.HYDROLOGY...
RAINFALL THIS AFTERNOON THROUGH TONIGHT WILL RANGE FROM LESS THAN
1/10 INCH WEST OF NYC...TO UP TO 1/4 INCH OVER EASTERN LONG
ISLAND/CT. NO SIGNIFICANT HYDROLOGIC IMPACT IS EXPECTED.

&&

.TIDES/COASTAL FLOODING...
STRONG WEST WINDS WILL LIKELY RESULT IN NEGATIVE TIDAL DEPARTURES OF 
2 TO 3 FT LATE TONIGHT AND SATURDAY. HOWEVER...ASTRONOMICAL TIDES 
NOT TOO LOW. FEEL BEST CHANCE FOR LOW WATER/BLOW OUT TIDES 
OCCURS SATURDAY AROUND LOW TIDE CYCLE...WHICH IS THIRD PERIOD. AS 
SUCH...STILL SOME TIME TO CONSIDER LOW WATER ADVISORY. WILL CONTINUE 
TO MONITOR.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY FROM 6 PM THIS EVENING TO NOON EST SATURDAY FOR 
     CTZ005>012.
NY...WIND ADVISORY FROM 6 PM THIS EVENING TO NOON EST SATURDAY FOR 
     NYZ067>081.
NJ...WIND ADVISORY FROM 6 PM THIS EVENING TO NOON EST SATURDAY FOR 
     NJZ002>006-011.
MARINE...SMALL CRAFT ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR ANZ330-
     335-338-340-345-350-353-355.
     GALE WARNING UNTIL 6 PM EST SATURDAY FOR ANZ330-335-338-340-
     345-350-353-355.

&&

$$
SYNOPSIS...AL
NEAR TERM...DW
SHORT TERM...PW
LONG TERM...
AVIATION...IRD
MARINE...PW
HYDROLOGY...
TIDES/COASTAL FLOODING...


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