Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 042342 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 742 PM EDT MON MAY 4 2015 .SYNOPSIS... HIGH PRESSURE REMAINS OVER THE ATLANTIC AS A COLD FRONT APPROACHES FROM THE NORTHWEST TONIGHT. THE COLD FRONT MOVES ACROSS THE AREA TUESDAY AND TUESDAY NIGHT. HIGH PRESSURE BUILDS OVER THE REGION FOR THE MIDDLE TO THE END OF THE WEEK. A FRONTAL BOUNDARY PASSES NORTH OF THE AREA THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... TEMPERATURES WERE PRETTY MUCH RIGHT IN LINE WITH FORECAST VALUES BUT DEWPOINTS HAD TO BE ADJUSTED SLIGHTLY DOWNWARD. OTHERWISE...NO OTHER SIGNIFICANT CHANGES MADE TO THE FORECAST DATABASE WITH THE FORECAST REMAINING ON TRACK. MODELS REMAIN IN GOOD AGREEMENT WITH SFC HIGH PRESSURE DRIFTING EAST TONIGHT OVER THE WESTERN ATLANTIC AS A COLD FRONT APPROACHES FROM THE NW. THE FRONT SHOULD MOVE INTO THE NW PORTION OF THE CWA BETWEEN 6 AND 10Z OVERNIGHT. ALOFT...RIDGE AXIS MOVES EAST THIS EVENING...WITH ZONAL FLOW PREVAILING ACROSS THE NORTHEAST FOR THE REMAINDER OF THE NIGHT. CLOSED LOW WELL UP IN EASTERN CANADA MOVES EAST. A GENERAL SW FLOW WILL DECREASE THROUGHOUT TONIGHT. MOSTLY CLEAR CONDITIONS WILL YIELD TO MORE CLOUDS AHEAD OF THE FRONT LATE TONIGHT. MESOSCALE MODELS INCLUDING ARW AND WRF-NMM SHOW SHOWERS ALONG AND AHEAD OF THE FRONT DISSIPATING AS THEY NEAR THE AREA LATE TONIGHT. NCEP MODELS INCLUDING SREF MEAN INDICATE LIGHT QPF VIA WEAKENING SHOWER ACTIVITY BEFORE 10Z TONIGHT...SO WILL MAINTAIN MINIMAL POPS FOR NW ZONES AS THEY NEAR THE AREA. ABOVE NORMAL TEMPS EXPECTED OVERNIGHT...WITH LOWS RANGING FROM AROUND 50 ACROSS THE INTERIOR TO THE LOWER 60S IN AND AROUND NYC. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... ZONAL FLOW INITIALLY WILL GIVE WAY TO A LATE DAY AND OVERNIGHT 500- 700 HPA TROUGH. THIS FEATURE IS MORE PRONOUNCED IN THE 12Z NAM. ANY MORNING ISOLATED SHOWER ACTIVITY WILL GIVE WAY TO SLIGHTLY HIGHER COVERAGE DURING THE AFTERNOON AND INTO THE EVENING HOURS. NAM...WRF-NMM SHOW CONVECTION UPSTREAM IN PA RIDING ALONG THE RIDGE EARLY IN THE DAY APPROACHING OUR REGION LATE. IT APPEARS THAT THE BETTER COVERAGE WILL BE JUST SOUTH OF THE FRONT FROM NE NJ/NYC SOUTHWARD. ECMWF/GFS AND SREF MEAN SUPPORT LESS COVERAGE WITH LOWER POPS. AT THIS TIME...WILL NOT STRAY TOO FAR FROM PREVIOUS FORECAST...RAISING POPS SLIGHTLY BUT CAPPING THEM IN THE CHANCE RANGE. HIGHEST POPS SW ZONES...AND LOWEST NE. THIS SUPPORTED BY LATEST DAY 2 SPC OUTLOOK FOR THUNDERSTORMS AS MARGINAL INSTABILITY IS PRESENT TO THE SOUTH AND WEST...IF NOT A LOT OF UPPER SUPPORT. DEPENDING ON THE LOCATION OF THE FRONT...ANY LINGERING SHOWER OR TSTM ACTIVITY WILL REMAIN OR PASS SOUTH TUESDAY NIGHT...WITH POPS LOWERING THROUGH THE NIGHT. EXPECT HIGH PRESSURE TO THE NORTH TO PUSH THE FRONT JUST TO OUR SOUTH DURING THE EVENING HOURS. ANOTHER UNSEASONABLY WARM DAY IS ON TAP DESPITE THE CLOUDS. READINGS MAY BE SLIGHTLY LOWER...BUT STILL EXPECT 80 DEGREES AWAY FROM THE WATER...WITH NEAR 70 OVER EASTERN SECTIONS OF THE CWA. WITH THE FRONT IN OUR PROXIMITY...WINDS WILL NOT BE AS STRONG...SO LESS DISPARITY IN TEMPS FROM WHAT OCCURRED EARLIER TODAY. TUESDAY LOWS WILL RUN ABOVE NORMAL...BUT WILL BE A FEW DEGREES COOLER THAN TONIGHT`S EXPECTED TEMPERATURES. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... COLD FRONT CONTINUES TO MOVE SOUTH AND EAST OF THE AREA WEDNESDAY MORNING. JUST A SLIGHT CHANCE FOR SOME LINGERING SHOWERS OVER SOUTHEAST ZONES IN THE MORNING...AND THEN CONDS CLEAR OUT FOR THE AFTERNOON. HIGH PRES BOTH AT THE SURFACE AND ALOFT WILL BUILD EAST AND OVER THE AREA FOR THE MIDDLE TO THE END OF THE WEEK...AND THEN THE HIGH MOVES OFFSHORE ON FRIDAY. DRY CONDS WITH NEAR TO ABOVE NORMAL TEMPS THROUGH THE END OF THE WORK WEEK WITH HIGHS GENERALLY IN THE 70S...WARMING INTO THE LOWER 80S ACROSS THE INTERIOR BY FRIDAY. WITH A LIGHT PRES GRADIENT...CAN EXPECT AFTERNOON SEA BREEZES...RESULTING IN COOLER AFTERNOON TEMPS FOR COASTAL AREAS. LOW PRES SLOWLY TRACKS THROUGH THE GREAT LAKES AND INTO THE OHIO VALLEY FOR THIS WEEKEND...AND A FRONTAL BOUNDARY WILL EXTEND FROM THIS SYSTEM AND MOVE WELL NORTH OF THE REGION. SATURDAY SHOULD BE DRY...BUT THE FRONT WILL BEGIN TO SAGE TO THE SOUTH FOR SUNDAY AND MONDAY...AND SCATTERED SHOWERS AND AFTERNOON THUNDERSTORMS ARE POSSIBLE FOR THE START OF THE NEW WEEK. WILL CAP POPS AT LOW CHANCE FOR NOW...WITH HIGHEST POPS ACROSS THE INTERIOR...WHICH WILL BE CLOSER TO THE FRONT. NEAR TO ABOVE NORMAL TEMPS WILL LIKELY CONTINUE FOR THE WEEKEND AND START OF THE NEW WEEK. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/...
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HIGH PRESSURE MOVES OFF THE COAST THIS EVENING AS A WEAK FRONTAL BOUNDARY APPROACHES. THE FRONT MOVES INTO THE AREA TOWARD 10Z TUESDAY AND REMAINS IN THE VICINITY THROUGH THE REMAINDER OF THE FORECAST PERIOD. WITH THE FRONTAL BOUNDARY IN THE VICINITY THE WIND FORECAST AT ALL THE TERMINALS WILL BE TOUGH AND HAVE LOW TO MODERATE CONFIDENCE. THERE IS LITTLE FORCING WITH THE FRONT AND THE CHANCE OF SHOWERS WILL BE LOW AND ACTIVITY IS EXPECTED TO BE SCATTERED. SO FORECAST WITH THE VICINITY SHOWERS. THE BETTER FORCING AND INSTABILITY WILL BE NEAR THE COST AND INDICATED A CHANCE OF THUNDER ALSO WITH VICINITY. CONDITIONS REMAIN VFR WITH A LOW CHANCE OF MARGINAL VFR IF A HEAVIER SHOWER OF THUNDERSTORM DOES HAPPEN TO MOVE THROUGH ONE PARTICULAR TERMINAL. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: NO UNSCHED AMD EXPECTED THIS EVENING. LOW CONFIDENCE ON THE WIND FORECAST FOR TUESDAY...AS WILL BE DEPENDENT ON WHERE WEAK FRONTAL BOUNDARY SETS UP. WITH WEAK FLOW TOMORROW A SEA BREEZE IS LIKELY. HIGHER CONFIDENCE IN SEA BREEZE DEVELOPMENT. KLGA FCSTER COMMENTS: NO UNSCHED AMD EXPECTED THIS EVENING. LOW CONFIDENCE ON THE WIND FORECAST FOR TUESDAY...AS WILL BE DEPENDENT ON WHERE A WEAK FRONTAL BOUNDARY SETS UP. WITH WEAK FLOW HAVE MODERATE CONFIDENCE THAT A SEA BREEZE WILL MOVE THROUGH THE TERMINAL...AND MAY BE EVEN LATER THAN FORECAST AT THIS TIME. KEWR FCSTER COMMENTS: NO UNSCHED AMD EXPECTED THIS EVENING. LOW CONFIDENCE ON THE WIND FORECAST FOR TUESDAY...AS WILL BE DEPENDENT ON WHERE A WEAK FRONTAL BOUNDARY SETS UP. KTEB FCSTER COMMENTS: NO UNSCHED AMD EXPECTED THIS EVENING. LOW CONFIDENCE ON THE WIND FORECAST FOR TUESDAY...AS WILL BE DEPENDENT ON WHERE A WEAK FRONTAL BOUNDARY SETS UP. KHPN FCSTER COMMENTS: NO UNSCHED AMD EXPECTED THIS EVENING. MODERATE CONFIDENCE ON THE WIND FORECAST FOR TUESDAY...AS WILL BE DEPENDENT ON WHERE A WEAK FRONTAL BOUNDARY SETS UP...MODERATE CONFIDENCE THE FRONT WILL BE SOUTH OF THE TERMINAL. KISP FCSTER COMMENTS: NO UNSCHED AMD EXPECTED THIS EVENING. MODERATE CONFIDENCE ON THE LLWS THIS EVENING. LOW CONFIDENCE ON THE WIND FORECAST FOR TUESDAY...AS WILL BE DEPENDENT ON WHERE WEAK FRONTAL BOUNDARY SETS UP. WITH WEAK FLOW TOMORROW A SEA BREEZE IS LIKELY. HIGHER CONFIDENCE IN SEA BREEZE DEVELOPMENT. .OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY... .TUESDAY NIGHT THROUGH SATURDAY...VFR.
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&& .MARINE... SW GUSTS NEAR 20-25 KT THIS EVENING ACROSS THE NEARSHORE WATERS WILL GRADUALLY LOWER THIS EVENING. THE 25KT GUSTS ARE EXPECTED TO BE GENERALLY OCCASIONAL IN FREQUENCY. IN ADDITION...OCEAN SEAS PER WAVE WATCH III BUILD TO 5 FT TONIGHT WHERE SCA REMAINS IN EFFECT. ELSEWHERE...SOUTH TO SOUTHWEST FLOW WILL LIGHTEN AS THE NIGHT PROGRESSES. A COLD FRONT APPROACHES AND TRACKS JUST NORTH OF THE WATERS TUESDAY...AND SETTLES OVERHEAD TUESDAY NIGHT. WINDS LIGHTEN AND WILL EVENTUALLY SHIFT AROUND TO THE N/NE LATE TUESDAY NIGHT...DEPENDING ON THE EXACT LOCATION OF THE FRONT. && .FIRE WEATHER... GUSTY SW WINDS AND LOW RELATIVE HUMIDITY WARRANTS RED FLAG WARNING INTO THE EVENING FOR WESTERN ZONES. SPECIAL WEATHER STATEMENT ELSEWHERE FOR MARGINAL CONDITIONS. INTERIOR AREAS WILL LOWER WITH WINDS FIRST THIS EVENING WITH GUSTS EXPECTED TO LOWER TO BELOW 25 MPH AFTER 8 PM. FARTHER EAST INTO NYC AND ACROSS THE COAST...IT WILL TAKE A LITTLE LONGER BUT RH IS EXPECTED TO RISE ABOVE 30 PERCENT WITH THE ONSHORE FLOW. WINDS DIMINISH OVERNIGHT...AND HUMIDITY LEVELS RISE...SO DO NOT FORESEE ANY FIRE RELATED HEADLINES THROUGH TUESDAY. WITH HIGH PRES AND A LIGHT PRES GRADIENT OVER THE WATERS FOR THE MIDDLE TO THE END OF THE WEEK...CAN EXPECT TRANQUIL CONDS DURING THE LONG TERM PERIOD. SOME AFTERNOON GUSTS TO 20 KT POSSIBLE ACROSS THE NEAR SHORE WATERS DUE TO SEA BREEZES. && .HYDROLOGY... GENERALLY EXPECT FROM 1/10 TO 1/4 INCH OF BASIN AVERAGE RAINFALL TUESDAY AND TUESDAY NIGHT FROM SCATTERED SHRA/ISOLD TSTMS. HOWEVER CANNOT COMPLETELY RULE OUT LOCALLY HEAVY RAINFALL IN ANY STRONGER CONVECTION. IF THIS DOES OCCUR OVER AN AREA...THEN LOCALIZED MINOR FLOODING OF URBAN AND POOR DRAINAGE AREAS WOULD BE POSSIBLE. THIS IS A LOW PROBABILITY THOUGH. DRY CONDITIONS ARE EXPECTED WEDNESDAY THROUGH THE WEEKEND. NEXT CHANCE FOR SHRA/TSRA WILL BE ON SUNDAY AND MONDAY. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR NYZ067>075- 176>179. NJ...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR NJZ002-004- 006-103>108. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ350-353-355. && $$ SYNOPSIS...MPS/PW NEAR TERM...JM/PW SHORT TERM...PW LONG TERM...MPS AVIATION...MET MARINE...JM/MPS/PW FIRE WEATHER... HYDROLOGY...MPS/PW

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