FXUS61 KOKX 071527
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1027 AM EST MON DEC 7 2009
.SYNOPSIS...
SURFACE HIGH PRESSURE DOMINATES THROUGH TUESDAY. DEEP LOW PRESSURE
PASSES TO THE NORTHWEST OF THE REGION ON WEDNESDAY. COLD HIGH
PRESSURE BUILDS INTO THE REGION FOR THE END OF THE WEEK INTO THE
WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST IN GOOD SHAPE. 12Z SOUNDING SUPPORTS CURRENT HIGHS...JUST
MADE SOME MINOR TWEAKS TO NEAR TERM HOURLY TEMPS/DEWS AS A FEW PLACES
WERE COLDER THAN FORECAST. SOME LIGHT RETURNS ON RADAR ACROSS
EASTERN PA...WESTERN NJ/NY...BUT OBS INDICATING THAT IT'S NOT
REACHING THE GROUND. WILL KEEP A DRY FORECAST...BUT WILL MONITOR
NW ZONES.
OTHERWISE...WEAK HIGH PRESSURE IN PLACE THROUGH THE DAY. MID
LEVEL SHORTWAVE APPROACHES FROM THE OHIO VALLEY THIS AFTN. PARTLY
SUNNY THIS MORNING WITH CLOUDS INCREASING FURTHER AS THE TROUGH
APPROACHES. MAV/NAM MOS BLEND LOOKED GOOD FOR TEMPS...WHICH IS
NEAR SEASONABLE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
SHORTWAVE PASSES TO THE NORTH TONIGHT...BUT COLUMN LOOKS TOO DRY FOR
PRECIP...SO WILL CONTINUE WITH A DRY FORECAST. TUESDAY SHOULD START
OUT MOSTLY SUNNY WITH CLOUDS INCREASING THROUGH THE DAY OUT AHEAD OF
THE NEXT SYSTEM.
STRONG LOW PRESSURE ENTERS THE GREAT LAKES REGION LATE TUESDAY NIGHT
WITH A SECONDARY LOW FORMING IN THE MID-ATLANTIC. MODELS IN GENERAL
ARE TRACKING THIS SECONDARY OVER OR JUST SOUTH OF THE CWA. POPS ARE
LIKELY TO CATEGORICAL BY WEDNESDAY MORNING...FOCUSED MAINLY AFTER
MIDNIGHT...EXCEPT EASTERN THIRD OF CWA...WHERE POPS INCREASE TO CHC.
CATEGORICAL POPS THEN EVERYWHERE ON WEDS...TAPERING TO CHC EARLY
EVENING WEDS...THEN DRY OVERNIGHT.
PRECIP TYPE IS A BIT OF A CHALLENGE TO FORECAST. BASED ON BOUNDARY
LAYER TEMPS...WET BULB ZERO HEIGHTS...AND FREEZING LEVEL
HEIGHTS...THE CITY...IMMEDIATE SUBURBS AND LONG ISLAND MAY START OUT
AS A MIX OF RAIN AND SNOW...BUT SHOULD BE SEEING ALL RAIN BY
WEDNESDAY MORNING. THE NORTHERN FRINGE ZONES LIKELY REMAIN AT SNOW
THROUGH THE ENTIRE NIGHT...WITH AREAS IN BETWEEN GOING FROM SNOW AT
THE ONSET TO A MIX OF RAIN AND SNOW BY MORNING. WITH AN ELEVATED
WARM LAYER FORECAST TO CLIMB NO HIGHER THAN 1C...WILL AT LEAST
MENTION SLEET IN THE FORECAST FOR THE FAR NW ZONES WEDNESDAY
MORNING. THIS WILL NEED TO BE WATCHED AS MODELS ARE SOMETIMES TOO
COLD IN THE ELEVATED WARM LAYER WHEN THERE IS A STRONG SW FLOW IN
THE LAYER...AND FREEZING RAIN MAY OTHERWISE BE POSSIBLE.
WENT ALONG THE LINES OF HPC GUIDANCE FOR QPF THROUGH 12Z WEDS...BUT
TWEAKED THE WESTERN PART THE CWA UPWARDS A LITTLE. FOR ORANGE AND
WESTERN PASSAIC...THIS MEANS THE LIKELIHOOD OF ADVISORY CRITERIA
SNOWFALL BEFORE A CHANGEOVER TO RAIN. AGAIN...THE POTENTIAL OF
FREEZING RAIN...ESPECIALLY ACROSS SOME OF THE HIGHER ELEVATIONS WILL
HAVE TO BE CONSIDERED. IT IS ALSO WITHIN THE REALM OF POSSIBILITY
THAT THESE 2 ZONES SEE WARNING CRITERIA SNOWFALL. TOO EARLY TO GO
WITH ADVISORIES...AND NOT ENOUGH CONFIDENCE TO GO WITH A WINTER
STORM WATCH FOR ORANGE AND WESTERN PASSAIC RIGHT NOW. SUB-ADVISORY
SNOWS ELSEWHERE FOR NOW...BUT THIS MAY CHANGE FOR SOME OF THE OTHER
NW ZONES.
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. WENT SLIGHTLY BELOW MOS GUIDANCE FOR
THURSDAY'S HIGHS.
LASTLY...LOOKS LIKE ONE TIDE CYCLE FOR THE SOUTH SHORE OF LONG
ISLAND WITH SOME MINOR EROSION ON WEDNESDAY.
&&
.LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE DOMINATES THROUGH AT LEAST SATURDAY WITH BELOW NORMAL
TEMPERATURES. LOW PRESSURE MAY AFFECT THE AREA SATURDAY NIGHT AND
SUNDAY...BUT WITH DISAGREEMENT AMONG THE FORECAST MODELS...WILL
CONTINUE WITH INHERITED "HIDDEN" SLIGHT CHANCE POPS FOR THE PERIOD.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
VFR THROUGH THE TAF PERIOD UNDER HIGH PRESSURE.
WINDS GENERALLY LIGHT SW THIS MORNING BECOMING W APPROACH OF A WEAK
TROUGH.
TAF COMMENTS (FORECASTER INSIGHT ON TIMING, CONFIDENCE, TRENDS AND GROUND OPS)
KEWR...FORECAST ON TRACK IN TERMS OF CIG/VIS. TIMING ON WIND
SHIFT TO NW TONIGHT A BIT TRICKY AND MAY OCCUR A FEW HOURS EARLIER
THAN FORECAST.
KEWR HOURLY WIND FORECAST
ALL WIND DIRECTIONS ARE TRUE...ADD 13 DEGREES FOR MAGNETIC
07/12Z 00000KT
07/13Z 00000KT
07/14Z 22004KT
07/15Z 22007KT
07/16Z 22006KT
07/17Z 22007KT
07/18Z 22007KT
07/19Z 22007KT
07/20Z 23007KT
07/21Z 24008KT
07/22Z 25008KT
07/23Z 26008KT
KJFK...FORECAST ON TRACK TODAY WITH NO UNSCHEDULED
AMENDMENTS ANTICIPATED. TIMING ON WIND SHIFT TO NW THIS EVENING A
BIT UNCERTAIN.
KLGA...FORECAST ON TRACK TODAY WITH NO UNSCHEDULED
AMENDMENTS ANTICIPATED. TIMING ON WIND SHIFT TO NW THIS EVENING A
BIT UNCERTAIN.
KTEB...FORECAST ON TRACK TODAY WITH NO UNSCHEDULED
AMENDMENTS ANTICIPATED. TIMING ON WIND SHIFT TO NW THIS EVENING A
BIT UNCERTAIN.
KHPN...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS
ANTICIPATED.
KSWF...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS
ANTICIPATED.
KISP...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS
ANTICIPATED.
KBDR...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS
ANTICIPATED.
KGON...FORECAST ON TRACK...NO UNSCHEDULED AMENDMENTS
ANTICIPATED.
OUTLOOK 06Z TUESDAY THROUGH FRIDAY...
MON NIGHT-TUE...VFR.
TUE NIGHT-WED...IFR WITH GUSTY WINDS. WINTRY PRECIP N OF KNYC
TERMINALS.
THU...VFR WITH GUSTY W WINDS.
FRI...VFR.
&&
.MARINE...
LIGHT WINDS AND LOW SEAS TODAY AS HIGH PRESSURE TRANSITS ACROSS THE
WATERS. WINDS AND SEAS INCREASE TONIGHT AHEAD OF TROUGH OF LOW
PRESSURE AND INCREASING PRESSURE GRADIENT BETWEEN HIGH PRESSURE
BEHIND THE TROUGH AND A STRENGTHENING LOW WELL EAST OF CAPE
COD...BUT REMAIN BELOW SCA VALUES. GUSTY (SUB-SCA) NW WINDS TUESDAY
MORNING IN RESPONSE TO LOW LEVEL COLD ADVECTION...THEN WINDS
DIMINISH TUESDAY AFTERNOON AS HIGH PRESSURE BUILDS OVER THE WATERS.
WIND GUSTS INCREASE TO SCA LEVELS OVER THE COASTAL OCEAN WATERS AND
SOUND/BAYS AROUND EASTERN LONG ISLAND LATE TUESDAY NIGHT IN RESPONSE
TO AN INCREASING PRESSURE GRADIENT BETWEEN HIGH PRESSURE TO THE
NORTHEAST AND A STRONG LOW OVER THE GREAT LAKES.
WINDS CONTINUE TO INCREASE WEDNESDAY AS THE LOW TRACKS INTO SOUTHERN
CANADA AND A COASTAL LOW TRACKS OVER THE WATERS...WITH GUSTS...IF
NOT SUSTAINED WINDS TO AT LEAST SMALL CRAFT ON ALL WATERS...AND
GUSTS TO GALE FORCE WEDNESDAY MORNING ON THE COASTAL OCEAN
WATERS...SOUND...AND BAYS AROUND EASTERN LONG ISLAND (IN RESPONSE TO
STRONG LOW LEVEL EASTERLY FLOW AHEAD OF SURFACE WARM FRONT/COASTAL
LOW). WINDS THEN REMAIN AT SMALL CRAFT LEVELS ON GUSTY WEST WINDS
INTO FRIDAY AS THE INLAND LOW SLOWLY LIFTS NORTH-NORTHEAST.
DEPENDING ON THE STRENGTH OF LOW LEVEL WINDS...GALE CONDITIONS ARE
ALSO POSSIBLE WEDNESDAY NIGHT AND THURSDAY...ESPECIALLY OVER THE
COASTAL OCEAN WATERS.
THESE STRONG GUSTY WINDS WILL BUILD SEAS TO 7-11 FT EAST OF MORICHES
INLET/5-8 FT WEST OF MORICHES INLET BY WEDNESDAY...WITH SEAS OF 3-6
FT ON SOUND. SEAS ABOVE SCA LEVELS THEN CONTINUE INTO FRIDAY.
THIS PERSISTENT STRONG WEST FLOW OVER THE WATERS WEDNESDAY NIGHT
THROUGH FRIDAY COULD CREATE BLOW OUT TIDES FROM LATE THURSDAY INTO
FRIDAY AS WELL.
&&
.HYDROLOGY...
AROUND AN INCH OF LIQUID EQUIVALENT PRECIPITATION IS FORECAST FOR
TUESDAY NIGHT THROUGH WEDNESDAY...HOWEVER UP TO AN INCH AND A HALF
COULD BE POSSIBLE. MINOR URBANIZED FLOODING WOULD BE THE MOST LIKELY
IMPACTS FROM RAINFALL.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$