FXUS61 KOKX 091636
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1136 AM EST WED DEC 9 2009
.SYNOPSIS...
A STRONG LOW PRESSURE SYSTEM TRACKS ACROSS THE GREAT LAKES...AND
A SECONDARY LOW TRACKS TOWARD LONG ISLAND BY THIS AFTERNOON...AND
NEAR BOSTON BY THIS EVENING. THESE TWO STORMS WILL SLOWLY LIFT TO
OUR NORTH TONIGHT. HIGH PRESSURE BUILDS IN FROM THE WEST THROUGH
SATURDAY NIGHT...THEN SLIDES OFFSHORE SUNDAY. A COASTAL LOW COULD
THEN IMPACT THE AREA EARLY NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BACK EDGE OF PRECIP SHIELD WILL SHORTLY PASS EAST OF THE REGION.
WIND ADVISORY CONTINUES UNTIL 1 PM FOR ERN CSTL LOCATIONS AHEAD OF
WARM FRONT/LOW. THEN A LULL IN WINDS EXPECTED.
TEMPS HAVE JUMPED NEAR THE COAST...AND HAVE UPDATED DATABASE TO
ACCOUNT FOR CURRENT TRENDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
CROSSING COLD FRONT COUPLED WITH LF QUADRANT OF 150+ KNOT 300 HPA
JET WARRANTS CHANCE POPS FOR SHOWERS THIS EVENING. ENOUGH COLD
AIR COULD WORK IN ACROSS THE NORTHERN TIER THAT THEY COULD MIX
WITH/CHANGE TO SNOW SHOWERS BEFORE ENDING THERE. WINDS INCREASE
WITH STRONG COLD ADVECTION AND HAVE ISSUED WIND ADVISORY FOR THE
SAME AREA AS THE CURRENT ONE + ESSEX AND UNION COUNTIES IN NJ
FROM 8PM TONIGHT THROUGH 6AM THURSDAY WITH WEST WINDS OF 25-30
MPH GUSTING TO 45 TO 50 MPH EXPECTED. WINDS SHOULD DIMINISH
ENOUGH IN LOW LEVELS...THAT WHILE GUSTY WINDS WILL CONTINUE INTO
FRIDAY...THEY SHOULD REMAIN BELOW ADVISORY LEVELS.
OTHER THAN THE WIND...THE MAIN STORY IN THE SHORT TERM WILL BE
BELOW NORMAL TEMPERATURES...AS THE COLDEST AIR MASS OF THE FALL
BUILDS INTO THE REGION AHEAD OF CANADIAN HIGH PRESSURE BUILDING IN
FROM THE WEST. EXPECT HIGHS THURSDAY TO STRUGGLE TO REACH THE
UPPER 30S/AROUND 40...LOWS THURSDAY NIGHT IN THE TEENS ACROSS THE
INTERIOR AND 2OS ELSEWHERE (ABOUT 10 DEGREES BELOW NORMAL) WITH
WIND CHILLS FROM THE SINGLE DIGITS TO LOWER TEENS). HIGHS FRIDAY
WILL STRUGGLE TO REACH THE UPPER 20S ACROSS THE INTERIOR AND THE
FREEZING MARK ELSEWHERE (12-15 DEGREES BELOW NORMAL) AND WIND
CHILLS INN THE TEENS. LOWS FRIDAY NIGHT WILL BE SIMILAR TO
THURSDAY NIGHT...EXCEPT OVER LONG ISLAND...WHERE DIMINISHING
WINDS WILL ALLOW FOR THE PINE BARRENS TO COOL OFF LIKE THE
INTERIOR. WIND CHILLS WILL BE IN THE SINGLE DIGITS FRIDAY NIGHT.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
00Z ECMWF/GFS HAVE CHANGED THEIR TUNE FROM THE 12Z VERSIONS...SO
HAVE TWEAKED THE EXTENDED TOWARDS THE NEW RUNS. FIRST CHANGE WAS
TO DELAY THE IMPACT OF THE COASTAL LOW FOR EARLY NEXT WEEK TO
SUNDAY NIGHT/MONDAY (SHOULD BE DRY BEFORE THEN). LOOKS LIKE IT
WILL BE COLD ENOUGH FOR A LIGHT SNOW AT MOST LOCATIONS (COASTAL
LOW CURRENTLY FORECAST TOO FAR S FOR ANYTHING MORE THAN THAT)
ECMWF/GFS DIVERGE AFTER THAT IN TERMS OF TIMING SYSTEMS (THOUGH
DO AGREE ON A WARMER SOLUTION THAN THE 12Z MODELS) SO BASICALLY
HAVE PUT IN SLIGHT CHANCE POPS MONDAY/TUESDAY AND TRENDED
TEMPERATURES UPWARDS (THOUGH NOT AS WARM AS 00Z GUIDANCE SUGGESTS
TO HELP GUARD AGAINST ANY FLIP-FLOPS WITH FUTURE RUNS).
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
CHANGEOVER TO RAIN COMPLETE ACROSS THE REGION...AND BACK EDGE OF
PRECIP IS APPROACHING NYC TERMINALS.
BASED ON LATEST DATA...WIND FCST ON TRACK FOR TEB/EWR AND INLAND
TAF SITES. FOR NYC...STRONGER WINDS EXPECTED TO END IN THE NEXT
FEW HOURS. THE PERIOD OF S-SE WINDS IN THE TAF IS THE MOST
UNCERTAIN...AND DIRECTIONS MAY BE ERRATIC ONCE SPEEDS DECREASE.
CIGS MAY BE VARIABLE...AND COULD END UP IN THE LOW END OF MVFR
THROUGH THIS AFTERNOON...BUT THE GENERAL TREND WILL BE IMPROVING
CONDITIONS.
ALSO...LLWS IN TAFS ALSO INDICATIVE OF MECHANICAL TURBULENCE IN
ADDITION TO LLWS. TRUE LLWS MORE LIKELY IF SFC WINDS DECREASE.
TAF COMMENTS (FORECASTER INSIGHT ON TIMING, CONFIDENCE, TRENDS AND GROUND OPS)
KEWR...UNSCHEDULED AMENDMENTS MAY BE REQUIRED TO ADJUST
TIMING/DURATION OF IFR/LIFR CONDITIONS...AND FOR WINDS AS SFC LOW
PASSES BY THIS AFTERNOON.
KEWR HOURLY WIND FORECAST
ALL WIND DIRECTIONS ARE TRUE...ADD 13 DEGREES FOR MAGNETIC
09/14Z 07018KT
09/15Z 04005KT
09/16Z VRB07KT
09/17Z 25008KT
09/18Z 25007KT
09/19Z 25007KT
09/20Z 26005KT
09/21Z 26007KT
09/22Z 26008KT
09/23Z 27009KT
10/00Z 27011KT
10/01Z 27014KT
KJFK...UNSCHEDULED AMENDMENTS MAY BE REQUIRED TO ADJUST
TIMING/DURATION OF IFR/LIFR CONDITIONS...AND FOR WINDS AS SFC LOW
PASSES BY THIS AFTERNOON.
KLGA...UNSCHEDULED AMENDMENTS MAY BE REQUIRED TO ADJUST
TIMING/DURATION OF IFR/LIFR CONDITIONS...AND FOR WINDS AS SFC LOW
PASSES BY THIS AFTERNOON.
KTEB...UNSCHEDULED AMENDMENTS MAY BE REQUIRED TO ADJUST
TIMING/DURATION OF IFR/LIFR CONDITIONS...AND FOR WINDS AS SFC LOW
PASSES BY THIS AFTERNOON.
KHPN...UNSCHEDULED AMENDMENTS MAY BE REQUIRED MAINLY FOR
WINDS AS SFC LOW PASSES BY THIS AFTERNOON.
KSWF...UNSCHEDULED AMENDMENTS POSSIBLE FOR SFC WINDS. ALSO
MAY SEE A PERIOD OF LOWER VIS DUE TO FOG DEVELOPING OVER SNOW COVER.
KISP...UNSCHEDULED AMENDMENTS MAY BE REQUIRED TO ADJUST
TIMING/DURATION OF IFR/LIFR CONDITIONS...AND FOR WINDS/CHANCE
THUNDER AS SFC LOW PASSES BY THIS AFTERNOON.
KBDR...UNSCHEDULED AMENDMENTS MAY BE REQUIRED TO ADJUST
TIMING/DURATION OF IFR/LIFR CONDITIONS...AND FOR WINDS AS SFC LOW
PASSES BY THIS AFTERNOON.
KGON...UNSCHEDULED AMENDMENTS MAY BE REQUIRED TO ADJUST
TIMING/DURATION OF IFR/LIFR CONDITIONS...AND FOR WINDS/CHANCE
THUNDER AS SFC LOW PASSES BY THIS AFTERNOON.
OUTLOOK 15Z THU THROUGH SUNDAY...
THU-FRI...VFR WITH GUSTY W WINDS.
FRI NIGHT-SAT...VFR WITH DIMINISHING WINDS.
SUN...SUB-VFR POSSIBLE.
&&
.MARINE...
GALE WARNING REMAINS UNCHANGED. THERE WILL BE A LULL IN THE WINDS
FROM AROUND MIDDAY THROUGH THIS EARLY EVENING AS A SECONDARY LOW
PRESSURE CENTER PASSES THROUGH THE WATERS. BEHIND THE STORM...HIGH
PRESSURE BUILDS IN AND THE PRESSURE GRADIENT RE- TIGHTENS WITH A
GUSTY WESTERLY FLOW THIS EVENING. FORECAST SOUNDINGS SHOW THE
BOUNDARY LAYER WELL-MIXED FOR SEVERAL HOURS. GALE WARNING WILL
PROBABLY NEED TO BE EXTENDED INTO THURSDAY NIGHT ACROSS THE OCEAN
ZONES. WILL LET LATER SHIFTS REASSESS THIS.
SEAS EXPECTED TO BUILD UP TO 12 TO 16 FT RANGE TODAY. ALTHOUGH
WAVES IN THE SURF ZONE MAY APPROACH 8 FT ALONG THE SOUTH SHORE OF
LONG ISLAND...DOMINANT WAVE PERIOD IS FORECAST TO REMAIN BELOW 10
SECONDS AS WINDS SHIFT OFFSHORE THIS AFTERNOON. WILL THEREFORE
HOLD OFF ON ISSUING A HIGH SURF ADVISORY.
THE PROLONGED TIGHT PRESSURE GRADIENT SHOULD HAVE WINDS AT LEAST
UP TO SMALL CRAFT ADVISORY LEVELS THROUGH FRIDAY NIGHT. WINDS AND
SEAS THEN DIMINISH THROUGH THE DAY ON SATURDAY WITH THE CENTER OF
THE BUILDING HIGH CLOSER TO THE EASTERN SEABOARD. A COASTAL STORM
MAY BUILD WINDS AND SEAS AGAIN SATURDAY NIGHT INTO SUNDAY.
&&
.HYDROLOGY...
HEAVY QPF WILL PUSH EAST TODAY. AS SUCH...CONDITIONS IMPROVE THIS
AFTERNOON.
&&
.TIDES/COASTAL FLOODING...
WINDS WILL DIMINISH AS THEY SHIFT INTO AN OFFSHORE DIRECTION
BEFORE THE HIGH TIDE CYCLE THIS AFTERNOON. SO ALTHOUGH TIDAL
DEPARTURES ARE CURRENTLY 3 TO 4 FT THIS MORNING EXPECTING THEM TO
FALL TO 2 TO 2 1/2 FT INTO EARLY THIS AFTERNOON AS WIND SHIFTS
AND PRESSURE RISE. A SHORT FUSE COASTAL FLOOD ADVISORY FOR LOW
END MINOR COASTAL FLOODING HAS BEEN ISSUED FOR THE SOUTH SHORE
BAYS...EASTERN BAYS AND NY HARBOR. WITH HIGH TIDE LATE THIS
AFTERNOON FOR WESTERN SOUND...TIDAL DEPARTURES SHOULD BE ABLE TO
FALL BELOW MINOR THRESHOLDS.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR CTZ009>012.
WIND ADVISORY FROM 8 PM THIS EVENING TO 6 AM EST THURSDAY FOR
CTZ009>012.
NY...WIND ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NYZ078>081.
WIND ADVISORY FROM 8 PM THIS EVENING TO 6 AM EST THURSDAY FOR
NYZ071>081.
COASTAL FLOOD ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
NYZ072-074>077-079>081.
NJ...WIND ADVISORY FROM 8 PM THIS EVENING TO 6 AM EST THURSDAY FOR
NJZ005-006-011.
COASTAL FLOOD ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
NJZ006.
MARINE...GALE WARNING UNTIL 6 AM EST THURSDAY FOR ANZ330-335-338-340-
345-350-353-355.
&&
$$
SYNOPSIS...PFM
NEAR TERM...PW
SHORT TERM...PFM
LONG TERM...PFM
AVIATION...BS
MARINE...NV
HYDROLOGY...PFM
TIDES/COASTAL FLOODING...
