Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 231106 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 606 AM EST SUN NOV 23 2014 .SYNOPSIS... A WARM FRONT SLOWLY APPROACHES FROM THE SOUTHWEST THROUGH THIS EVENING...THEN LIFTS TO THE NORTH LATE TONIGHT AND MONDAY MORNING. A COLD FRONT FOLLOWS BEHIND IT MONDAY NIGHT...THEN A SECONDARY COLD FRONT PASSES ON TUESDAY. WEAK HIGH PRESSURE THEN BUILDS IN TUESDAY NIGHT. AN AREA OF LOW PRESSURE OFF THE SOUTHEASTERN SEABOARD WEDNESDAY MORNING...TRACKS NORTHEAST TO THE CANADIAN MARITIME PROVINCES BY THURSDAY EVENING. HIGH PRESSURE THEN BUILDS IN FROM THE WEST INTO FRIDAY...FOLLOWED BY A ALBERTA CLIPPER SYSTEM IMPACTING THE AREA SATURDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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MINOR CHANGES MADE THIS UPDATE TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. THE FORECAST APPEARS ON TRACK. CURRENTLY SEE NO EVIDENCE IN THE OBSERVATIONS THAT SPOTTY RELATIVELY WEAK RADAR RETURNS CLIPPING FAR N PORTIONS OF THE CWA...ARE PRODUCING ANY PRECIPITATION EARLY THIS MORNING BASED ON SURROUNDING OBSERVATIONS. BASED ON THIS...AND THAT SUPPORTING SHORTWAVE SHOULD BE EXITING TO THE EAST BY 12Z...HAVE GONE WITH A DRY FORECAST FOR THE IMMEDIATE NEAR TERM. EVEN IF A SPRINKLE DID OCCUR...TEMPERATURES ABOVE ABOVE FREEZING AND WILL REMAIN SO. OTHERWISE...A DEEP LAYERED RIDGE BUILDS OVER THE AREA TODAY. WILL SEE DECREASING CLOUD COVER IN RESPONSE TO ASSOCIATED SUBSIDENCE WITH AREAS PARTLY TO MOSTLY SUNNY BY LATE AFTERNOON. FOR HIGHS TODAY...USED A BLEND OF MAV/MET/ECS GUIDANCE WITH NAM 2-METER TEMPERATURES AND A MIX DOWN FROM 975 HPA PER BUFKIT SOUNDINGS. HIGHS SHOULD BE NEAR TO SLIGHTLY ABOVE NORMAL.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
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THE DEEP LAYERED RIDGE LIFTS TO THE NORTHEAST THIS EVENING...ALLOWING FOR LOW-MID LEVEL MOISTURE TO QUICKLY BUILD IN BEHIND IT. WITH DIFFLUENT FLOW DEVELOPING ALOFT AND PASSAGE OF A 60-70 KT LOW LEVEL JET...EXPECT MODERATE...TO POSSIBLY LOCALLY HEAVY...RAINFALL OVERSPREADING THE ENTIRE AREA AFTER MIDNIGHT AHEAD OF THE SURFACE-850 HPA WARM FRONT. THERE IS SUFFICIENT ELEVATED INSTABILITY OVER EASTERN ZONES...WITH SHOWALTER INDICES FORECAST TO BETWEEN 0 AND 2...ALONG WITH THE AFOREMENTIONED LOW LEVEL JET...THAT HAVE CONTINUED WITH A SLIGHT CHANCE OF THUNDER THERE. PRECIPITATION SHOULD TAPER OFF TO -SHRA BY LATE MONDAY MORNING AS THE WARM FRONTS LIFT TO THE NE. REFER TO THE HYDROLOGY SECTION OF THE AFD FOR DETAILS ON AMOUNTS AND ANY POTENTIAL IMPACTS. ALSO WITH THE PASSAGE OF THE AFOREMENTIONED LOW LEVEL JET...THERE COULD BE ISOLATED WIND GUSTS OF 40-50 MPH IN ANY EMBEDDED CONVECTION...WITH THE BEST CHANCE OVER EASTERN ZONES LATE TONIGHT/MONDAY MORNING - AND DAMAGING WIND GUSTS CANNOT BE 100 PERCENT RULED OUT. IT SHOULD END UP QUITE WINDY ONCE IN THE WARM SECTOR MONDAY AFTERNOON AND EVENING...WITH GUSTS UP TO 30-40 MPH. ISOLATED STRONGER GUSTS ARE POSSIBLE...HOWEVER CONFIDENCE IN THERE OCCURRENCE AND AREAL COVERAGE IS NOT HIGH ENOUGH TO WARRANT A WIND ADVISORY AT THIS TIME. FOR LOWS TONIGHT A BLEND OF MAV/MET/ECS GUIDANCE AND NAM 2-METER TEMPERATURES WAS USED...WITH VALUES FORECAST TO BE AROUND 10-15 DEGREES ABOVE NORMAL. EXPECT THE LOWS TO OCCUR IN THE EVENING...THEN TEMPERATURES TO RISE INTO THE 50S OVERNIGHT...EXCEPT MID-UPPER 40S FAR NW ORANGE COUNTY. RECORD HIGHS QUITE POSSIBLY WILL BE SET ON MONDAY AT MANY LOCATIONS...WITH THE REGION SOLIDLY IN THE WARM SECTOR IN THE AFTERNOON. THE MAIN QUESTION IS HOW MUCH CLEARING WILL OCCUR ONCE THERE. FOR NOW APPEARS SHOULD BE SUFFICIENT TO SUPPORT HIGHS AROUND 15-20 DEGREES ABOVE NORMAL. THIS IS CONSISTENT WITH A BLEND OF MAV/MET/ECS GUIDANCE WITH A MIX DOWN FROM 975-950 HPA PER BUFKIT SOUNDINGS AND NAM 2-METER TEMPERATURES. REFER TO THE CLIMATE SECTION OF THE AFD FOR DETAILS. SHOULD HAVE SUFFICIENT LOW LEVEL MOISTURE TO SEE AN ISOLD-SCT SHRA AHEAD OF THE COLD FRONT MONDAY EVENING. THEN CLEARING IN ITS WAKE. FOR LOWS MONDAY NIGHT A BLEND OF MAV/MET/ECS GUIDANCE AND NAM 2-METER TEMPERATURES WAS USED...WITH VALUES FORECAST TO BE AROUND 15 DEGREES ABOVE NORMAL. TUESDAY WILL FEATURE SW FLOW ALOFT...AND AS CURRENTLY FORECAST TO BE ABSENT ANY SHORTWAVES EMBEDDED IN THE FLOW...IT SHOULD BE DRY. FOR HIGHS USED A BLEND OF MIXING DOWN FROM 900-850 HPA PER BUFKIT SOUNDINGS WITH MAV/MET GUIDANCE AND NAM 2-METER TEMPERATURES. HIGHS SHOULD BE A FEW DEGREES ABOVE NORMAL.
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&& .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... THERE ARE STILL DIFFERENCES BETWEEN THE MODELS...BUT NOW THE RESPECTIVE ENSEMBLE MEANS GENERALLY SUPPORTING THE GFS (THOUGH THE ECMWF ENSEMBLE MEAN IS FARTHER W). WITH THE GFS AND CMC TRENDING STRONGER (AROUND 10 MB DEEPER THAN LAST NIGHT) AND FARTHER WEST...HAVE OPTED TO USE A ECMWF/GFS BLEND AS THERE IS INCREASING EVIDENCE THAT A SOLUTION IN BETWEEN THE TWO SEEMS THE MOST REASONABLE. UNTIL ALL THE KEY PLAYERS...INCLUDING ENERGY STILL OUT OVER THE PACIFIC ARE RESOLVED...THE EXACT NATURE OF INTERACTION BETWEEN A NORTHERN STREAM CLIPPER AND A POSITIVELY TILTED TROUGH OVER THE E CENTRAL PORTION OF THE COUNTRY BY MIDWEEK IS STILL UNCERTAIN - SO THE FORECAST WILL LIKELY CHANGE TO SOME DEGREE. FOR NOW THOUGH THE FOLLOWING IS WHAT APPEARS MOST LIKELY - THAT A FAIRLY DECENT...BUT NOT OVERLY STRONG LOW SHOULD TRACK JUST EAST OF THE 40N/70W BENCHMARK WEDNESDAY EVENING. THE BLEND WOULD SUGGEST THAT LIGHT RAIN COULD REACH LONG ISLAND AND MAYBE FAR SE CT LATE TUESDAY NIGHT POSSIBLY MIXED WITH SNOW. THE PRECIPITATION SHOULD THEN SPREAD NW FAIRLY QUICKLY WEDNESDAY MORNING...POSSIBLY STARTING AS A BRIEF PERIOD OF SNOW INLAND BEFORE TURNING TO ALL RAIN. AS THE LOW NEARS THE BENCHMARK WEDNESDAY EVENING...ENOUGH LOW LEVEL COLD AIR SHOULD COME IN BEHIND IT TO CHANGE ALL PRECIPITATION TO SNOW DURING WEDNESDAY NIGHT...FROM NW TO SE...THROUGHOUT THE CWA. THE EXACT TIMING OF THIS IS UNCERTAIN. PRECIPITATION SHOULD TAPER OFF FROM SW TO NE THURSDAY MORNING...UNLESS THE DEFORMATION AXIS LINGERS OVER THE AREA...WHICH IS SUGGESTED BY THE ECMWF. FOR THIS REASON JUST WENT WITH SLIGHT CHANCE POPS THROUGH THE DAY. THE ECMWF TAKEN BY ITSELF WOULD SUGGEST THE POSSIBILITY OF WARNING LEVEL SNOWS TO THE W/N OF NYC...WHILE THE GFS SOLUTION SUGGESTS THE POSSIBILITY OF WARNING LEVEL SNOWS FARTHER EAST. GIVEN THIS...THERE IS A 30 PERCENT CONFIDENCE OF REACHING WARNING LEVEL SNOW ACCUMULATIONS ACROSS THE CWA...SO WILL REFLECT THIS IN THE HWO. FORTUNATELY IT LOOKS LIKE MOST...IF NOT ALL...ACCUMULATING SNOW WILL OCCUR MAINLY WEDNESDAY NIGHT SO THE IMPACT ON THE BULK OF PRE-THANKSGIVING TRAVEL SHOULD BE MINIMIZED. ZONAL THEN SW FLOW BUILDS IN BEHIND THE SYSTEM INTO FRIDAY...THEN A WEAK ALBERTA CLIPPER PASSES TO THE N ON SATURDAY...POSSIBLY LEADING TO COASTAL DEVELOPMENT NEAR CAPE COD. BASED ON THIS HAVE SLIGHT CHANCE POPS IN OVER EASTERN ZONES FRIDAY NIGHT AND SATURDAY...WITH THE CLIPPER ITSELF LIKELY PASSING TO FAR N TO BRING ANY PRECIPITATION BY ITSELF UNTIL THE COASTAL LOW FORMS. FOR TEMPERATURES TUESDAY NIGHT-SATURDAY A BLEND OF MEX/MEN/EKD/ECE/ECM/WPC GUIDANCE WAS USED...WITH NAM 2-METER TEMPERATURES BLENDED IN TUESDAY NIGHT AND GFS AND ECMWF 2-METER TEMPERATURES BLENDED IN WEDNESDAY AND WEDNESDAY NIGHT. TEMPERATURES WILL REMAIN BELOW NORMAL THROUGH THE LONG TERM. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... HIGH PRES REMAINS OFFSHORE TODAY. A WARM FRONT APPROACHES AND PASSES THROUGH TONIGHT. VFR THROUGH AROUND 03Z MONDAY. SW WINDS WILL GENERALLY AVERAGE AROUND 10 KT INTO THE AFTERNOON. GUIDANCE CONTINUES TO HINT AT POSSIBLE SEA BREEZES AT KHPN TO KGON WITH LI SOUND TEMPS IN THE 40S. THIS WOULD BACK WINDS TO AROUND 170 TRUE AFT 17Z. WINDS WILL OTHERWISE BACK TO THE SOUTH TOWARDS EVENING. CIGS GRADUALLY LOWER TO MVFR/IFR BETWEEN 03-06Z MONDAY AS WARM FRONT APPROACHES FROM THE SOUTH. .OUTLOOK FOR 06Z MONDAY THROUGH THURSDAY... .TONIGHT-MONDAY...IFR OR LOWER IN RAIN/FOG. LLWS POSSIBLE WITH 50-65 KT WINDS 1500-2000 FT LATE TONIGHT THROUGH MONDAY MID-MORNING. HIGHEST EAST. SOUTH WINDS AROUND 20 KT WITH 20-35 KT GUSTS. .MONDAY NIGHT...IMPROVING CONDS. WINDS SHIFT TO THE WEST AT 10-15 KT. .TUESDAY...VFR. WEST WINDS 15-20 KT WITH 20-30 KT GUSTS. .TUESDAY NIGHT...DIMINISHING WINDS. SUB-VFR CIGS POSSIBLE LATE. .WEDNESDAY-WEDNESDAY NIGHT...LOW TO MODERATE CONFIDENCE FORECAST WITH PASSAGE OF COASTAL LOW. ACCUMULATING SNOW THREAT POSSIBLE FOR THE INTERIOR...BUT ACCUMULATING SNOW COULD OCCUR CLOSER TO THE COAST DURING WEDS NIGHT BASED ON TRACK OF LOW. STRONG WINDS POSSIBLE DEPENDING ON TRACK OF LOW AS WELL. .THURSDAY...LOW CONFIDENCE FORECAST. LINGERING RAIN/SNOW SHOWERS POSSIBLE. STRONG WINDS POSSIBLE AS WELL. && .MARINE...
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SEAS AT 44097 REMAIN AT 7FT AND AT 44025 AT 8 FT...WITH GUSTS TO 25 KT AT 44065 AT 5 AM. THEREFORE WILL EXTEND THE SCA FOR ANZ-355 UNTIL 9AM. LATEST OBSERVATIONS THOUGH INDICATE WIND GUSTS ON THE NON- OCEAN WATERS HAVE FALLEN BELOW 25 KT...SO HAVE ALLOWED THE SCA THAT WAS UP THERE TO EXPIRE. STILL APPEAR ON TRACK FOR SCA CONDITIONS THOUGH MIDDAY FOR ANZ350-353. SEAS MIGHT TAKE AN HOUR OR TWO PAST THE SCA END TIME TO FALL BELOW 5 FT ON THE OCEAN WATERS...SO SCA END TIMES MIGHT BE FURTHER ADJUSTED LATER THIS MORNING. A RELATIVELY TRANQUIL PERIOD THEN FOLLOWS THIS AFTERNOON INTO THIS EVENING AS A HIGH PRESSURE RIDGE PIVOTS THROUGH. WINDS PICK UP LATE TONIGHT INTO MON MORNING WITH A TIGHTENING PRESSURE GRADIENT AND THE APPROACH AND PASSAGE OF A 950MB LOW LEVEL JET OF 60-70KT. HAVE THEREFORE GONE WITH A GALE WARNING FOR THE OCEAN WATERS...EASTERN LONG ISLAND SOUND...AND THE LONG ISLAND BAYS LATE AT NIGHT THROUGH MONDAY AFTERNOON. SCA FOR THE OTHER WATERS DURING THE SAME PERIOD. ALTHOUGH WINDS DIMINISH MONDAY NIGHT...SCA CONDITIONS STILL PROBABLE FOR ALL WATERS THROUGH AT LEAST TUESDAY MORNING. SEAS ON THE OCEAN WILL TAKE LONGER THAN THIS TO SUBSIDE BELOW 5 FT. LOOKS LIKE BY MIDNIGHT TUESDAY NIGHT...ALL WATERS WILL BE BELOW ADVISORY CRITERIA. THE NEXT STORM AFFECTS THE WATERS LATE WEDS AFTERNOON THROUGH THURS WITH A COASTAL STORM PASSING NEARBY THE 40N/70W BENCHMARK WEDS NIGHT. FOR NOW...SCA CONDITIONS FORECAST...BUT THERE IS POTENTIAL FOR GALES. CONFIDENCE NOT HIGH AT THIS TIME.
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&& .HYDROLOGY... AROUND 3/4 TO 1 INCH OF RAIN IS FORECAST FROM LATE TONIGHT THROUGH MONDAY. ANY LOCALLY HEAVY RAINFALL MAY RESULT IN URBAN/POOR DRAINAGE FLOODING LOCALLY. THE HEAVIEST RAIN WILL OCCUR DURING THE MORNING RUSH HOUR MONDAY MORNING...WITH THE MOST LIKELY IMPACT BEING TO SLOW THE COMMUTE DUE TO WET ROADS. THERE IS INCREASING POTENTIAL FOR 1/2 INCH OR MORE OF QPF TO FALL FROM LATE TUESDAY NIGHT INTO THURSDAY MORNING. AT THIS TIME THERE IS TOO MUCH UNCERTAINTY TO SPECIFY ANY IMPACT...OTHER THAN TO NOTE THAT SOME PORTION OF THIS SHOULD FALL IN THE FORM OF SNOW. AT THIS TIME IT APPEARS THAT THE BEST CHANCE OF GETTING MORE THAN 1/2 INCH OF QPF WOULD BE OVER LONG ISLAND AND S CT. && .CLIMATE... RECORD HIGH TEMPERATURES FOR MONDAY 24 NOVEMBER... LOCATION........RECORD/YEAR.....FORECAST HIGH NEWARK..............75/1979..........71 BRIDGEPORT..........63/1979..........65 CENTRAL PARK........73/1979..........69 LAGUARDIA AIRPORT...68/1999..........70 JFK AIRPORT.........63/2001*.........68 ISLIP...............63/2001..........66 * ALSO OCCURRED IN PREVIOUS YEARS && .OKX WATCHES/WARNINGS/ADVISORIES...
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CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 6 PM EST MONDAY FOR ANZ335- 338. SMALL CRAFT ADVISORY UNTIL 9 AM EST THIS MORNING FOR ANZ355. GALE WARNING FROM 1 AM TO 6 PM EST MONDAY FOR ANZ330-340-345- 350-353-355. SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR ANZ350-353.
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&& $$ SYNOPSIS...MALOIT NEAR TERM...MALOIT SHORT TERM...MALOIT LONG TERM...MALOIT AVIATION...JC MARINE...MALOIT/JC HYDROLOGY...MALOIT CLIMATE...MALOIT

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