FXUS61 KOKX 082059
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
359 PM EST TUE DEC 8 2009

.SYNOPSIS...
HIGH PRESSURE SLIDES NORTHEAST TONIGHT INTO THE CANADIAN MARITIMES
TONIGHT. INTENSE LOW PRESSURE OVER THE CENTRAL PLAINS MOVES INTO
THE GREAT LAKES TOMORROW...WITH A SECONDARY LOW DEVELOPING OFF THE
NJ COAST. THIS LOW MOVES ACROSS LONG ISLAND AND RACES INTO NEW
ENGLAND BY TOMORROW EVENING. HIGH PRESSURE WILL RETURN FOR THE
REST OF THE WORK WEEK...BUT ANOTHER STORM COULD IMPACT THE AREA
THIS WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
DRY SEASONABLY COOL WEATHER TODAY WITH JUST HIGH CLOUDS. EXPECT
SKIES TO BECOME OVERCAST THIS EVENING WITH WARM AIR ADVECTION
ALOFT STRENGTHENING AS A POTENTIALLY HIGH IMPACT SYSTEM MOVES UP
OUT OF THE CENTRAL PLAINS. 

RADIATIONAL COOLING SHOULD BE SOMEWHAT LIMITED BY INCREASING CLOUD
COVER...BUT NOT ENOUGH TO PREVENT TEMPS FROM FALLING BELOW
FREEZING FOR THE INTERIOR LOWER HUDSON VALLEY AND CT. 

WAA ALOFT INCREASES IN EARNEST AFTER ABOUT 9PM AND EXPECT PRECIP TO
FLY IN BY MIDNIGHT OR SLIGHTLY AFTER. THIS IS A FEW HOURS FASTER
THAN THE OPERATIONAL MODELS...WHICH TEND TO BE TOO SLOW WITH THE
ONSET OF PRECIP IN STRONG WAA EVENTS.

PRECIP MAY START AS A BRIEF PERIOD OF SLEET/SNOW IN MANY PLACES
INCLUDING NYC...AS DEWPOINTS IN THE LOW TO MID 20S WOULD GIVE A
WETBULB TEMP IN THE LOW 30S. COASTAL SECTIONS WILL GO OVER TOO
RAIN ALMOST IMMEDIATELY HOWEVER. WINTRY WEATHER LASTS LONGER TO
THE NORTH. 

SNOWFALL RATES AND AMOUNTS ARE VERY COMPLEX. LL JET INCREASES TO
70+ KTS ACROSS A 15 DEG C GRADIENT OVERNIGHT...INDICATING INTENSE
LIFT AND THE POTENTIAL FOR HEAVY PRECIP. IF THE COLD COLUMN IS
DEEP ENOUGH TO SUPPORT SNOW THROUGH 4-6AM...THE LIFT MAY BE STRONG
ENOUGH TO SUPPORT RATES OF 1-2 INCHES PER HOUR. GIVEN HOW STRONG
THE WARNING IS...DID NOT INCLUDE THESE TYPE OF ACCUMULATIONS IN
THE FORECAST...BUT IT SHOULD BE NOTED. 

SO...THE WINTER WEATHER ADVISORY REMAINS AS IS. SOME OF THE DEEPER
VALLEYS IN ORANGE AND PASSAIC COUNTIES MAY SEE A BIT MORE
ICING...ESPECIALLY IF SFC TEMPS DIP A FEW DEGREES LOWER THAN
FORECAST THIS EVENING.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
STRONG WARMING CONTINUES INTO THE MORNING...AND ONCE THE SFC WARM
FRONT MATERIALIZES...THERE COULD BE A VERY RAPID CHANGEOVER TO ALL
RAIN. AGAIN...THIS MAY OCCUR A FEW HOURS PRIOR TO OR AFTER THE
CURRENT FORECAST...BUT THE TREND IS FOR A CHANGE TO ALL LIQUID.

TOTAL SNOWFALL OF UP TO 5 INCHES IN ORANGE/PASSAIC...BUT WOULD NOT
BE SURPRISED IF A FEW SPOTS SAW MORE. 

ANOTHER ISSUE IS WIND SPEEDS. AS THE TEMP RISES ALOFT...IT WILL BE
TOUGH TO MIX DOWN STRONGER WINDS. HOWEVER...FOR A FEW HOURS PRIOR
TO THE PASSAGE OF THE WARM FRONT...THERE MAY BE ENOUGH INSTABILITY
TO GET ADVISORY LEVEL WINDS NEAR THE COAST. WIND ADVISORY HOISTED
TO ADDRESS THIS THREAT. THERE MAY ALSO BE ROUGH SURF/BEACH EROSION
PROBLEMS WEDNESDAY MORNING GIVEN STRONG EAST TO SOUTHEAST WINDS
AND 6 TO 9 FT NEAR SHORE BREAK. 

PRECIP SHOULD WIND DOWN DURING WED AFTERNOON AS THE SECONDARY LOW
PASSES OVER LONG ISLAND. BOTH OPERATIONAL NAM AND GFS BRING DRY
AIR INTO THE REGION BY LATE AFTERNOON WEDNESDAY.

STRONGEST COLD AIR ADVECTION IS ABOUT 12 HOURS BEHIND THE
SYSTEM...SO TEMPS NOT EXPECTED TO DROP RIGHT AWAY. 

TEMPS ALOFT PLUNGE THURSDAY...SO EXPECT A PRETTY FLAT TEMP TREND
DURING THE DAY...AND COLD TEMPS THURSDAY NIGHT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL BUILD INTO THE CWA BEHIND THE DEPARTING LOW....
AND REMAIN THROUGH SATURDAY NIGHT...PROVIDING FAIR AND DRY
CONDITIONS...BUT WITH GUSTY W WINDS CONTINUING THU INTO FRI. 
IT WILL BE COOL...WITH HIGHS ONLY REACHING THE UPPER 30S AND
LOWER 40S...WITH OVERNIGHT LOWS FALLING INTO THE TEENS AND 20S.

AN AREA OF LOW PRESSURE MAY IMPACT THE CWA SAT NIGHT INTO
SUNDAY...AND THERE IS SOME DISAGREEMENT AMONG THE FORECAST MODELS
AS TO THE EXACT TRACK THIS LOW TAKE...AND JUST HOW CLOSE IT WILL
COME. FOR NOW WILL CARRY JUST SLIGHT CHANCE POP SAT NIGHT...AND
INCREASE TO CHANCE POP DURING SUNDAY. HIGH PRESSURE SHOULD RETURN
SUNDAY NIGHT INTO MON.

&&

.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
HIGH PRESSURE OVER THE AREA TERMINALS WILL MOVE NORTHWARD THIS 
EVENING. A HIGH IMPACT COASTAL LOW WILL MOVE ACROSS THE AREA 
TERMINALS TONIGHT THROUGH WEDNESDAY. 

MVFR-IFR/PRECIPITATION WILL OVERSPREAD THE REGION BETWEEN 04Z AND 
07Z TONIGHT...WITH A BRIEF PERIOD OF SLEET POSSIBLE. PRECIPITATION 
WILL START AS A MIX OF RAIN AND SNOW AT KHPN...AND ALL SNOW AT KSWF. 
ALL RAIN IS EXPECTED ELSEWHERE. LIFR WILL BE LIKELY AT KSWF FOR A 
PERIOD OF TIME BETWEEN 09Z AND 13Z WHEN SNOW IS FALLING. 

PRECIPITATION BECOMES ALL RAIN BY 14Z AT ALL THE TERMINALS...WITH 
SOME OF THE RAIN HEAVY AT TIMES. 

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

KEWR...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KEWR HOURLY WIND FORECAST
ALL WIND DIRECTIONS ARE TRUE...ADD 13 DEGREES FOR MAGNETIC
     08/18Z 34006KT    
     08/19Z 35005KT    
     08/20Z 02005KT    
     08/21Z 04004KT    
     08/22Z 06004KT    
     08/23Z 09004KT    
     09/00Z 10004KT    
     09/01Z 10005KT    
     09/02Z 09005KT    
     09/03Z 09006KT    
     09/04Z 09006KT    
     09/05Z 08007KT    

KJFK...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KLGA...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KTEB...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KHPN...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KSWF...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KISP...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KBDR...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

KGON...NO UNSCHEDULED AMENDMENTS EXPECTED. IFR MAY LAST A 
FEW HOURS LONGER DURING WEDNESDAY MORNING.

OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY... 

WEDNESDAY AFTERNOON...STRONG AND VERY GUSTY EAST-NORTHEAST WINDS 
INTO THE AFTERNOON. 
WEDNESDAY NIGHT...BECOMING VFR EARLY WITH GUSTY WSW WINDS 
DEVELOPING. 
THURSDAY-FRIDAY...VFR WITH GUSTY W WINDS.
FRIDAY NIGHT-VFR WITH DIMINISHING WINDS. 
SATURDAY...SUB VFR POSSIBLE.

&&

.MARINE...
PRESSURE GRADIENT RAPIDLY STRENGTHENS OVERNIGHT AHEAD OF A COMPLEX 
LOW PRESSURE SYSTEM TRACKING NE TOWARDS THE GREAT LAKES AND HIGH 
PRESSURE SLOWLY SLIDING NE. EXPECTING EASTERLY WINDS ON ALL WATERS 
TO INCREASE TO GALE LATE TONIGHT AHEAD OF ASSOC WARM FRONT AND 
CONTINUE THROUGH AROUND 18Z AT WHICH TIME LLJ LIFTS N. EXPECTING 
SEAS ON THE OCEAN TO RAPIDLY INCREASE TO 14 TO 17 FT IN RESPONSE.

WINDS WILL LIKELY FALL TO SCA LEVEL FOR A 6 TO 9 HR PERIOD WED 
AFTERNOON INTO EARLY WED EVE AS WARM FRONT MOVES THROUGH...BEFORE 
PICKING UP AGAIN TO GALE WED NIGHT ON ALL WATERS IN WAKE OF COLD 
FRONT WITH STRONG CAA. GALES MAY CONTINUE INTO FRI...ESPECIALLY 
OCEAN WATERS WITH PROLONGED PERIOD OF CAA AND TIGHT WESTERLY 
GRADIENT IN WAKE OF SLOWLY DEPARTING LOW AND STRONG HIGH PRESSURE 
OVER TENNESSEE VALLEY. SEAS REMAINING HIGH...PARTICULARLY EASTERN 
WATERS.   

RELATIVELY QUIET CONDITIONS ON SATURDAY AS HIGH PRESSURE BUILD IN. 
THEN WINDS AND SEAS MAY BUILD AGAIN SATURDAY NIGHT AND SUNDAY WITH 
THE POTENTIAL OF A COASTAL STORM AFFECTING THE REGION.

&&

.HYDROLOGY...
2 TO 2.5 INCHES LIQUID/LIQUID EQUIVALENT PRECIPITATION IS FORECAST FOR
TUESDAY NIGHT THROUGH WEDNESDAY...WITH LOCALLY HIGHER AMOUNTS
POSSIBLE. WHILE THE MAIN IMPACT IS EXPECTED TO BE URBAN/SMALL
STREAM FLOODING...IT COULD BE WIDESPREAD ENOUGH TO HAVE
SIGNIFICANT IMPACT ON THE MORNING RUSH. A FLASH FLOOD WATCH HAS
BEEN ISSUED. 

QPF AMOUNTS SHOULD BE MAXIMIZED DURING THE 5AM TO 11AM TIMEFRAME.
0.5 TO 1.0 INCH PER HOUR RATES ARE POSSIBLE DURING THIS PERIOD.

&&

.TIDES/COASTAL FLOODING...
MAIN CONCERN FOR COASTAL FLOODING WILL BE THE TIMES OF HIGH TIDE IN 
WESTERN LONG ISLAND SOUND EARLY WED MORNING WHERE AROUND 2 FT 
DEPARTURES ARE NEEDED FOR MINOR COASTAL FLOODING. WINDS AND PRESSURE 
FALLS WILL JUST BE GETTING GOING AT THAT TIME...SO THINKING IS THAT 
WE WILL GET CLOSE TO MINOR COASTAL FLOODING LEVELS...BUT FALLING 
SHORT FOR THE MOST PART. ISOLATED MINOR IS POSSIBLE...BUT NOT ENOUGH 
CERTAINTY FOR ADVISORY.

WINDS ARE WEAKENING AND THEN TURNING SW FOR THE LATE 
AFTERNOON/EVENING HIGH TIDES...SO NOT EXPECTING US TO REACH THE 2 TO 
2 1/2 FT NEEDED FOR MINOR.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY FROM 4 AM TO 2 PM EST WEDNESDAY FOR CTZ009>012.
     FLASH FLOOD WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY 
     AFTERNOON FOR CTZ005>012.
NY...WIND ADVISORY FROM 4 AM TO 2 PM EST WEDNESDAY FOR NYZ071>081.
     FLASH FLOOD WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY 
     AFTERNOON FOR NYZ067>081.
     WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST 
     WEDNESDAY FOR NYZ067>070.
NJ...WIND ADVISORY FROM 4 AM TO 2 PM EST WEDNESDAY FOR NJZ006.
     FLASH FLOOD WATCH FROM WEDNESDAY MORNING THROUGH WEDNESDAY 
     AFTERNOON FOR NJZ002>006-011.
     WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST 
     WEDNESDAY FOR NJZ002.
MARINE...GALE WARNING FROM 3 AM WEDNESDAY TO 6 AM EST THURSDAY FOR 
     ANZ330-335-338-340-345-350-353-355.

&&

$$
SYNOPSIS...BS
NEAR TERM...BS/NV
SHORT TERM...BS/NV
LONG TERM...JM/NV
AVIATION...BC
MARINE...JM/NV
HYDROLOGY...BS/FIG
TIDES/COASTAL FLOODING...