000
FXUS61 KOKX 032148
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE UPTON NY
448 PM EST WED DEC 3 2008
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE SOUTHEAST COAST WEDNESDAY NIGHT
INTO THURSDAY AS A COLD FRONT APPROACHES FROM THE WEST. THE FRONT
MOVES THROUGH THE AREA LATE THURSDAY AFTERNOON INTO THE EARLY
EVENING. COLD CANADIAN HIGH PRESSURE BUILDS OVER THE REGION LATER
THURSDAY NIGHT INTO SATURDAY. AN ALBERTA CLIPPER WILL PASS THROUGH
THE REGION SATURDAY NIGHT INTO SUNDAY...FOLLOWED BY HIGH PRESSURE
BUILDING BACK MONDAY AND TUESDAY. ANOTHER COLD FRONT APPROACHES
FOR WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
SOUTHWESTERLY FLOW CONTINUES AS HIGH PRESSURE MOVES OFF THE
SOUTHEASTERN COAST. WINDS WILL BE INCREASING AS THE HIGH MOVES OFF
AND A COLD FRONT APPROACHES. CLOUDS WILL ALSO BE INCREASING.
STRONG WARM AIR ADVECTION WILL KEEP TEMPERATURE ALONG THE COAST
NEARLY STEADY OVERNIGHT...AND INLAND LOWS MAY BE THIS
EVENING...THEN TEMPERATURES COULD START TO RISE. HAVE NOT YET
INDICATED THIS IN THE GRIDS.
&&
.SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/...
MODELS FAIRLY CONSISTENT WITH THE TIMING OF THE FRONT THURSDAY
EVENING...AND THE GFS THE QUICKEST WITH THE PRECIPITATION. SOME
LINGERS BEHIND THE FRONT BUT NOT ENOUGH SUPPORT FOR STEADY
PRECIPITATION. SO END PRECIPITATION QUICKLY THURSDAY NIGHT. COLD
AIR COMING IN MAY CHANGE PRECIPITATION TO SOME LIGHT SNOW BEFORE
ENDING. CONTINUED WITH CHANCE POPS AS MOISTURES REMAINS WEAK. COLD
AND DRY WEATHER MOVES IN BEHIND THE FRONT THURSDAY NIGHT INTO
SATURDAY. USED A BLEND OF FWC AND ETA NUMBERS FOR TEMPERATURES
THROUGH THE PERIOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
12Z ECMWF TRENDING WWD WITH SFC LOW...SIMILAR TO THE IDEA OF THE 6Z
DGEX. STILL A SPREAD IN THE ENSEMBLES AND OPERATIONAL MODELS. MAIN
ISSUE IS WHETHER THERE WILL BE A MDT BAND TO SET UP. REGARDLESS OF
THIS BAND...EXPECT LGT SN ACROSS THE CWA AFT MIDNIGHT SAT INTO SUN.
ATTM...MOST FAVORED AREAS FOR A MORE SIG EVENT IS ACROSS ERN LI AND
CT. THICKNESSES AND H85 TEMPS SUPPORTIVE OF ALL SN...UNLESS SOME
WARMER BL AIR WORKS IN ALONG THE IMMEDIATE ERN COASTS. 12Z ECMWF
WOULD PRODUCE 2-4IN SN NL COUNTY IN CT AND TWIN FORKS OF LI.
ANY PCPN TAPERS OFF SUN EVENING AND WINDS CRANK UP. THE MORE INTENSE
ECMWF BRINGS A CORE OF 50KT H85 WINDS THRU.
SPREAD IN THE PROGS REALLY INCREASE MON AND BEYOND. HIGH PRES WILL
BRING DRY WX WITH TEMPS BLW CLIMO FOR MON WITH DIMINISHING WINDS.
TIMING OF THE NEXT SYSTEM AND ACTUAL EVOLUTION REMAINS IN QUESTION.
SW FLOW ALOFT SHOULD TRANSPORT MOISTURE NWD WITH INCREASING CLOUDS
AND A SLIGHT CHANCE OF PCPN BY TUE AFTN. DRY AIR IN PLACE SHOULD
ALLOW FOR THE ONSET TO BE SN OR RASN. AS THE WAA ALOFT INCREASES
OVERNIGHT...INTERIOR SECTIONS MAY HAVE A FZ PCPN ISSUE. INCLUDED
FZRA AND IP IN THE FCST WITH RA COAST. 12Z ECMWF/GFS END PCPN WED
AFTN/EVE WITH CAA TO FOLLOW.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
VFR. WINDS HAVE BEGUN BACKING TO A WSW DIRECTION AT MOST
TERMINALS...BUT SHOULD HOLD OFF ON BACKING FULLY SW UNTIL CLOSE TO
SUNSET. SPEEDS PICK UP TO ABOUT 10-15 KT DURING THU MORNING AS
PRESSURE GRADIENT INCREASES AHEAD OF APPROACHING COLD FRONT...WITH
INCREASING HIGH/MID LEVEL CLOUDS.
OUTLOOK FOR 18Z THURSDAY THROUGH MON...COLD FRONT MOVES THROUGH LATE
THU AFTERNOON INTO THU NIGHT...FOLLOWED BY POST-FRONTAL SUB-VFR
CONDITIONS AND SCATTERED LIGHT RAIN/SNOW SHOWERS MAINLY DURING THE
FIRST HALF OF THE NIGHT. ALBERTA CLIPPER SYSTEM PASSING THROUGH
COULD BRING SOME LIGHT SNOW AND SUB-VFR CONDITIONS SAT NIGHT INTO
SUNDAY...FOLLOWED BY GUSTY NW WINDS LATE SUNDAY AFTERNOON INTO MON.
&&
.MARINE...
WIND GUSTS ON THE OCEAN WATERS REMAIN AROUND SMALL CRAFT
LEVELS...AND WINDS WILL BE INCREASING LATER TONIGHT ON ALL THE
AREA WATERS AS HIGH PRESSURE BUILDS SOUTH OF THE WATERS AND A
COLD FRONT APPROACHES FROM THE WEST. HAVE CONVERTED THE SMALL
CRAFT FOR SEAS TO A GENERIC ONE. WIND GUSTS ON THE OCEAN WATERS
REQCH GALE FORCE DURING THE DAY THURSDAY FOR SEVERAL HOURS. WIND
GUSTS ON THE REMAINDER OF THE WATERS WILL REACH SMALL
CRAFT...HOWEVER SOME GALE FORCE GUSTS WILL BE POSSIBLE ACROSS THE
EASTERN SOUND ZONE AND PECONIC AND GARDINERS BAYS FOR AN HOUR OR
TWO THURSDAY AFTERNOON. WITH THE PASSAGE OF THE COLD FRONT
LATE THURSDAY AFTERNOON INTO THE EARLY EVENING WINDS QUICKLY
DIMINISH...HOWEVER SMALL CRAFT GUSTS ARE LIKELY INTO THE EVENING.
HIGH PRESSURE BUILDS INTO THE WATERS FROM THE WEST THURSDAY NIGHT
INTO EARLY SATURDAY...THEN A CLIPPER SYSTEM APPROACHES LATER
SATURDAY.
SN WILL DEVELOP LATE SAT NIGHT. THE MOST FAVORED AREA FOR VSBY
RESTRICTIONS BLW 2NM WILL BE OVER THE OCEAN WITH THE POTENTIAL FOR
MDT SN. RA MAY MIX WITH THE SN OVER THE OCEAN ON SUN AS LOW PRES
DEEPENS OFFSHORE. AS THE PCPN TAPERS OFF LATE SUN/SUN EVE...WINDS
WILL INCREASE TO A SOLID GALE ACROSS ALL CSTL WATERS. LATEST DATA
INDICATES POSSIBLE 45KT WIND GUSTS OVER THE OCEAN. THE EXACT TRACK
AND TIMING OF THIS SYSTEM REMAIN UNCERTAIN...SO SOME CHANGES IN
THE FCST SHOULD BE ANTICIPATED.
GALES DIMINISH MON WITH SCA SEAS REMAINING ON THE OCEAN. HIGH PRES
THEN BUILDS IN FOR MON.
A COMPLEX STORM SYSTEM WILL IMPACT THE CSTL WATERS FOR MID
WEEK...STARTING AS EARLY AS TUE AFTN. WINDS AND SEAS WILL INCREASE
AGAIN.
&&
.HYDROLOGY...
LIGHT QPF STARTING THURSDAY AFTERNOON INTO THURSDAY NIGHT WITH UP
TO A TENTH OF AN INCH POSSIBLE. UP TO A QUARTER INCH QPF IS
POSSIBLE SATURDAY NIGHT AND SUNDAY WITH MOST FALLING IN THE FORM
OF SNOW. NO HYDROLOGIC PROBLEMS ARE ANTICIPATED.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 5 PM EST
THURSDAY FOR ANZ330-335-338-340-345.
SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ350-353.
GALE WARNING FROM 6 AM TO 5 PM EST THURSDAY FOR ANZ350-353-355.
SMALL CRAFT ADVISORY UNTIL 6 AM EST THURSDAY FOR ANZ355.
&&
$$
SYNOPSIS...MET
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...JMC
AVIATION...BG
MARINE...JMC/MET
HYDROLOGY...MET
