766 FXUS61 KOKX 020148 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE UPTON NY 848 PM EST MON DEC 1 2008 .SYNOPSIS... DEEP LOW PRESSURE WILL TRACK UP THE SAINT LAWRENCE RIVER VALLEY TONIGHT. HIGH PRESSURE WILL BUILD INTO THE TRI-STATE REGION FOR THE MIDDLE OF THE WEEK. A STRONG COLD FRONT LATE IN THE WEEK WILL USHER IN COLD WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... STRATO-CU AND ISOLATED SHRA ACTIVITY IS EXPECTED TO GRADUALLY DISSIPATE THIS EVENING AS LOW-LEVELS DRY OUT AND LOW-LEVEL INSTABILITY IS LOST. WIND GUSTS SHOULD DIMINISH ACROSS MOST OF THE REGION BY AROUND MIDNIGHT...EXCEPT NYC METRO WITH URBAN HEAT. TEMPS REMAIN ABOVE SEASONABLE LEVELS WITH MIXED LOW-LEVELS AND ONLY WEAK CAA. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... H5 TROF AXIS REACHES THE CWA LATE TUE. MOISTURE REMAINS LIMITED SO MAINTAINED THE DRY FCST. TEMPS COOLER BUT SEASONAL WITH H85 TEMPS -6 TO -7C. WSW WINDS A BIT LIGHTER AS THE PRES GRAD RELAXES. S/WV RIDGING ON WED. SFC HIGH EXPANDS NEWD FROM THE GOMEX. DRY WX AND SLIGHTLY MILDER FOR WED. 00Z ECMWF/12Z GFS/09Z SREF ALL CLOSE IN TIMING OF THE COLD FRONT THU AFTN. MOISTURE TRANSPORT AHEAD OF THE FRONT LOOKS LIMITED ATTM...SO A LIGHT PCPN EVENT WITH THE FROPA. IF TIMING OF A LATE AFTN PASSAGE HOLDS...MORE 50S LIKELY ACROSS MUCH OF THE CWA. THERE WILL BE A BKN-OVC HIGH CLOUD DECK AHEAD OF THE FRONT. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... GLOBAL MODELS ARE ALL IN GOOD AGREEMENT WITH AN ANOMALOUSLY COLD PATTERN THROUGH EARLY NEXT WEEK. THE MEAN UPPER TROF ESTABLISHES ITSELF FROM THE UPPER MIDWEST TO THE EASTERN SEABOARD WITH A STEADY DIET OF POLAR ENERGY REINFORCING THE COLD AIR IN PLACE. ON THE HEELS OF ONE COLD FRONTAL PASSAGE EARLY THU EVE...A CLIPPER LOW WILL DESCEND SE FROM THE GREAT LAKES ON SUN WITH ANOTHER SURGE OF POLAR AIR TO FOLLOW. IN BETWEEN...HIGH PRES WILL BUILD ACROSS THE AREA FOR FRI AND SAT. IN ADDITION...BOTH THE ECMWF AND GFS CONTINUE TO INDICATE A SECONDARY LOW DEVELOPING OFF THE SOUTHERN NEW ENGLAND COAST ON SUN. AS ALWAYS...THE QUESTION REMAINS AS TO HOW CLOSE AND RAPIDLY WILL IT DEVELOP TO PROVIDE WINTRY WEATHER FOR THE REGION. DUE TO THE PERSISTENCE OF THE MODELS WITH THIS FEATURE AND A STRONG UPPER TROUGH INTERACTING WITH ATLANTIC MOISTURE...LOW CHC POPS FOR SNOW HAVE BEEN INTRODUCED INTO THE FORECAST FOR THIS TIME. CPC 6 TO 10 DAY OUTLOOK CONTINUES TO CALL FOR BELOW NORMAL TEMPERATURES AND ABOVE NORMAL PRECIPITATION. && .AVIATION /02Z TUESDAY THROUGH SATURDAY/... DECREASING STRATO-CU AND ISOLATED SHRA ACTIVITY AS LOW-LEVELS DRY AND LOW-LEVEL INSTABILITY WANES THIS EVENING. REMAINS GUSTY UNTIL AT LEAST MIDNIGHT...PERHAPS LATER AT NYC TERMINALS VIA ENHANCED URBAN HEAT ISLAND MIXING. VFR WITH WSW FLOW OF 10-15 KT MOST PLACES SHOULD CONTINUE THROUGH OVERNIGHT...WITH GUSTS 20-25 KT RETURNING BY 14Z- 15Z WITH DAYTIME HEATING. GRADIENT RELAXES/CAA WANES TUES AFTERNOON WITH GUSTS BEING LOST. VFR SCT-BKN INSTABILITY CU EXPECTED TUES AFTERNOON...PARTICULARLY WESTERN TERMINALS. OUTLOOK FOR 00Z WED THROUGH SAT... A COLD FRONT COULD BE PRECEDED/ACCOMPANIED BY BRIEF SUB-VFR CONDITIONS IN SHOWERS THU AFTERNOON...AND FOLLOWED BY GUSTY W-NW WINDS THU NIGHT INTO FRI. && .MARINE... GALE WARNING WILL REMAIN IN PLACE FOR ALL WATERS EXCEPT THE WRN SOUND AND NY HARBOR. ANZ355 AND 345 MARGINAL FOR GALES WRN PORTIONS. SERN ANZ355 FAVORED FOR GALE FORCE GUSTS AND THE AREA NEAR SHINNECOCK INLET FAVORED FOR ANZ345. A SCA WILL BE NEEDED FOR ALL OCEAN ZONES AFT THE GALES SUBSIDE. SCA WINDS WILL END ACROSS HARBOR/WESTERN SOUND IN THE MORNING. WINDS WILL FALL BELOW SCA LVLS TUE NIGHT AND WED. ERN OCEAN ZONES HOWEVER WILL MAINTAIN SCA SEAS TUE NIGHT AND PERHAPS WED ACROSS EXTREME ERN SECTIONS. WED NIGHT SEAS SUBSIDE WITH HIGH PRES BUILDING NEWD ACROSS THE CSTL WATERS. A COLD FRONT WILL APPROACH THE WATERS LATE THU. SCA CONDITIONS WILL DEVELOP AHEAD OF THE FRONT. STRONG COLD ADVECTION THU NIGHT INTO THE FIRST HALF OF FRI WILL GENERATE SCA CONDITIONS ON THE WATERS...FOLLOWED BY HIGH PRESSURE BUILDING IN FRI AFT INTO SAT. A CLIPPER LOW SWINGS ANOTHER POLAR COLD FRONT ACROSS THE WATERS ON SUN WITH THE POTENTIAL FOR GALE CONDITIONS...OR AT THE VERY LEAST A SCA. && .HYDROLOGY... LESS THAN 1/2IN PCPN LOOKS LIKELY WITH A COLD FRONT LATE THU. NO FLOODING IS ANTICIPATED THROUGH THE FCST PERIOD. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TUESDAY FOR ANZ338. GALE WARNING UNTIL 10 AM EST TUESDAY FOR ANZ330-340-345-350- 353. SMALL CRAFT ADVISORY UNTIL NOON EST TUESDAY FOR ANZ335. GALE WARNING UNTIL 5 AM EST TUESDAY FOR ANZ355. && $$