FXUS61 KOKX 080120
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
820 PM EST MON DEC 7 2009
.SYNOPSIS...
AN UPPER DISTURBANCE PASSES TO THE NORTH TONIGHT. HIGH PRESSURE
THEN BUILDS IN FROM THE PLAINS TONIGHT AND TUESDAY AS STRONG LOW
PRESSURE ENTERS THE CENTRAL US. THE LOW LIFTS NORTHEAST INTO THE
GREAT LAKES REGION WHILE STRENGTHENING TUESDAY NIGHT AND
WEDNESDAY...WITH A WEAKER SECONDARY LOW DEVELOPING NEAR THE
VIRGINIA COAST. THIS COMPLEX STORM SYSTEM LIFTS INTO SOUTHEAST
CANADA WEDNESDAY NIGHT WITH HIGH PRESSURE RETURNING FOR THE
REMAINDER OF THE WORK WEEK. ANOTHER STORM COULD IMPACT THE AREA
THIS WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
SHORTWAVE TROUGH SLIDES NORTH OF THE AREA WITH MID AND HIGH
CLOUDS GRADUALLY DISSIPATING. WEAK LOW PRES SOUTH OF CAPE COD WILL
STRENGTHEN AS IT MOVES OUT TO SEA...AS HIGH PRES BUILDS IN FROM
THE TENNESSEE VALLEY. W WINDS TURN TO THE NW OVERNIGHT AND
INCREASE SLIGHTLY IN RESPONSE TO THE TIGHTENING GRADIENT. LOWS
TONIGHT WILL BE CHILLY...AND BELOW FREEZING AGAIN IN MOST
LOCALS...BUT SEASONABLE. EXTENT OF CLOUDS AND HOW QUICKLY THEY
DISSIPATE WILL PLAY A BIG ROLE IN MINS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
ALL ATTENTION THEN TURNS TO THE COMPLEX STORM SYSTEM LIFTING NE OUT
OF THE PLAINS AND INTO THE GREAT LAKES REGION ON TUE. MODELS ARE IN
RELATIVELY GOOD AGREEMENT WITH THE TRACK AND STRENGTH OF THE
SYSTEM...WITH WEAK SECONDARY LOW PRES DEVELOPMENT NEAR THE VA/DE
COAST LATE TUE NIGHT/WED MORNING. THIS SECONDARY LOW IS FORECAST
TO TRACK OVER THE LOCAL AREA DURING THE DAY WED...WITH BOTH
SYSTEMS LIFTING INTO SE CANADA WED NIGHT.
TUESDAY SHOULD START OUT MOSTLY SUNNY WITH CLOUDS INCREASING
THROUGH THE DAY.
WILL LIKELY HAVE P-TYPE ISSUES AWAY FROM THE IMMEDIATE COAST WITH
A RETREATING HIGH TO THE NORTHEAST. AN INCREASING E FLOW ADVECTING
AIR IN OFF THE WARMER OCEAN WATERS IS EXPECTED TO KEEP PRECIP ALL
OF THE LIQUID FORM ON LI...NYC AND POSSIBLY COASTAL CT. ONSET OF
PRECIP IS AROUND MIDNIGHT TUE NIGHT...SO FURTHER INLAND EXPECT
SNOW TO START. THE BOUNDARY LAYER GRADUALLY WARMS...ESPECIALLY
AFTER SUNRISE WITH A CHANGEOVER TO ALL RAIN EXPECTED ACROSS THE
CWA BY AFTERNOON. MODELS TYPICALLY DON'T HANDLE COLD AIR DAMMING
WELL...SO THE POTENTIAL FOR FREEZING RAIN IN AREAS NORTH AND WEST
OF NYC DEFINITELY EXISTS AND WILL NEED TO BE MONITORED.
TIMING OF TRANSITION MAKES FOR A TRICKY SNOWFALL FORECAST...BUT
HIGHEST CONFIDENCE OF ADVISORY CRITERIA CONTINUES TO BE IN ORANGE
AND WESTERN PASSAIC COUNTIES. IT IS ALSO WITHIN THE REALM OF
POSSIBILITY THAT THESE 2 ZONES SEE WARNING CRITERIA SNOWFALL. THIS
WILL DEPEND ON HOW QUICKLY THE HEAVIER PRECIP CAN MOVE IN BEFORE
THE CHANGEOVER. PUTNAM...ROCKLAND...N WESTCHESTER...N
FAIRFIELD...N NEW HAVEN ALSO HAVE A CHANCE TO REACH ADVISORY
LEVELS...BUT CONFIDENCE IS NOT AS HIGH. STILL TOO EARLY TO GO WITH
ADVISORIES...AND NOT ENOUGH CONFIDENCE TO GO WITH A WINTER STORM
WATCH FOR ORANGE AND WESTERN PASSAIC RIGHT NOW.
HIGH PRESSURE BUILDS IN AND WINDS PICK UP BEHIND THE DEPARTING STORM
WEDS NIGHT AND THURSDAY WITH A GUSTY WEST FLOW. SOME MOISTURE FROM
THE LAKES MAY BE TRANSPORTED OVER HERE...BUT PROBABLY RESULTS IN
NOTHING MORE THAN SOME CLOUDS. MAY EVENTUALLY NEED A WIND ADVISORY
DURING THIS PERIOD AS WELL.
LASTLY...LOOKS LIKE ONE TIDE CYCLE FOR THE SOUTH SHORE OF LONG
ISLAND WITH SOME MINOR TO MODERATE BEACH EROSION ON WEDNESDAY.
COASTAL FLOODING DOESN'T APPEAR TO BE AN ISSUE AS WE ARE BETWEEN
MOONS...2 FT DEPARTURES ARE NEEDED AND STRONG EASTERLY FLOW
WON'T LAST LONG ENOUGH TO CAUSE PROBLEMS.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BUILD INTO THE CWA BEHIND THE DEPARTING LOW. THIS
HIGH WILL REMAIN OVER THE REGION THROUGH SATURDAY NIGHT PROVIDING
FAIR AND DRY CONDITIONS. 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 SATURDAY NIGHT INTO
SUNDAY...HOWEVER AT THIS TIME THERE IS SOME DISAGREEMENT AMONG THE
FORECAST MODELS AS TO THE EXACT TRACK THIS LOW TAKE...AND JUST HOW
CLOSE IT WILL COME TO THE TRI-STATE AREA. FOR NOW WILL CARRY JUST
SLIGHT CHANCE POPS SATURDAY NIGHT...AND INCREASE TO CHANCE POPS
DURING THE SUNDAY. HIGH PRESSURE BUILDS BACK INTO THE REGION SUNDAY
NIGHT AND MONDAY.
&&
.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
VFR WITH MID AND HIGH CLOUDS EXPECTED TO GIVE WAY TO PARTIAL CLEARING.
LIGHT WEST WINDS 5 TO 10 KTS SHOULD TURN TO THE NORTHWEST 5 TO 10
KTS AFTER MIDNIGHT. WINDS GENERALLY TO THE LEFT OF 310 DEGREES. BY
MORNING...AFTER SUNRISE...WINDS VEER JUST TO THE RIGHT OF 310...5
TO 10 KTS. HIGH PRESSURE BUILDS...AND WINDS LIGHTEN AFTER 3 PM.
SCATTERED CLOUDS.
OUTLOOK 00Z WEDNESDAY THROUGH SATURDAY...
TUE NIGHT-WED MORNING...VFR QUICKLY TO IFR WITH GUSTY E-NE WINDS.
WINTRY PRECIP N OF KNYC TERMINALS.
WED AFTN-FRI...VFR WITH GUSTY W WINDS...ALTHOUGH WINDS DIMINISH
BY FRI.
SAT...SUB VFR POSSIBLE.
&&
.MARINE...
TRANQUIL CONDITIONS CONTINUE ON THE WATERS INTO TUE NIGHT. WINDS AND
SEAS THEN INCREASE LATE TUE NIGHT...LIKELY REACHING GALE FORCE
RATHER QUICKLY. THEREFORE...HAVE HOISTED A GALE WATCH FOR ALL
WATERS FROM LATE TUE NIGHT THROUGH WED. GALES WILL LIKELY
NEED TO BE EXTENDED INTO WED NIGHT.
GALE GUSTS LIKELY CONTINUE INTO FRIDAY NIGHT AS THE AREA WATERS
WILL BE IN BETWEEN THE DEPARTING LOW PRESSURE SYSTEM AND
APPROACHING HIGH. WINDS AND SEAS ARE EXPECTED TO FALL BELOW SCA
LEVELS SATURDAY NIGHT INTO SUNDAY. ANOTHER STORM SYSTEM MAY IMPACT
THE AREA WATERS ON SUNDAY...WHICH MAY ALLOW WINDS AND SEAS TO
RETURN TO SCA LEVELS.
&&
.HYDROLOGY...
AN INCH TO AN INCH AND A HALF OF LIQUID EQUIVALENT PRECIPITATION
IS FORECAST FOR TUESDAY NIGHT THROUGH WEDNESDAY...HOWEVER UP TO AN
TWO INCHES IS POSSIBLE. MINOR URBANIZED FLOODING WOULD BE THE
MOST LIKELY IMPACTS FROM RAINFALL.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...GALE WATCH FROM LATE TUESDAY NIGHT THROUGH WEDNESDAY AFTERNOON
FOR ANZ330-335-338-340-345-350-353-355.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...PW
MARINE...
HYDROLOGY...
