Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 221753 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 153 PM EDT FRI MAY 22 2015 .SYNOPSIS... A COLD FRONT MOVES ACROSS THE AREA LATE TODAY. HIGH PRESSURE BUILDS ACROSS THE AREA OVER THE WEEKEND. OFFSHORE HIGH PRESSURE SETS UP TO CLOSE OUT THE WEEKEND AND REMAINS IN PLACE THROUGH MUCH OF NEXT WEEK. A WARM FRONT APPROACHES SUNDAY NIGHT AND MOVES ACROSS MONDAY NIGHT. A COLD FRONT APPROACHES FOR LATE NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... FORECAST ON TRACK WITH NO SIGNIFICANT CHANGES TO THE FORECAST. CLOUDS INCREASE A BIT THIS AFTERNOON AS A COLD FRONT OUT AHEAD OF A DIGGING TROUGH APPROACHES THE AREA. A FEW SHOWERS ARE POSSIBLE AHEAD OF THE FRONTAL PASSAGE ALONG WITH A GUSTY WEST TO NORTHWEST FLOW THIS AFTERNOON AND INTO THIS EVENING. MAX TEMPERATURES TODAY WILL BE IN THE LOW TO MID 70S. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... GUSTY WIND CONDITIONS EXPECTED TONIGHT...AS A COLD FRONT MOVES ACROSS THE AREA. AGAIN...A FEW SHOWERS ARE POSSIBLE WITH THE FRONTAL PASSAGE EARLY IN THE EVENING. BEHIND THE FRONTAL PASSAGE...EXPECT MAINLY DRY WEATHER CONDITIONS TONIGHT WITH COLD NIGHTTIME TEMPERATURES IN THE UPPER 30S AND 40S. DRY AND BREEZY CONDITIONS ARE EXPECTED ON SATURDAY AS HIGH PRESSURE BUILDS INTO THE AREA. HIGHS ON SATURDAY WILL BE IN THE MID AND UPPER 60S...WITH LOWS IN THE 40S AND 50S. HIGH PRESSURE SHIFTS OFFSHORE SATURDAY NIGHT WITH DRY WEATHER CONTINUING. WINDS OUT OF THE SOUTHWEST WILL KEEP A RELATIVELY MORE MILD AIRMASS WITH LOW TEMPERATURES A FEW DEGREES WARMER THAN THOSE OF THE PREVIOUS NIGHT. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE JET STREAM WILL BE PUSHING NORTH OF THE REGION SUNDAY AND REMAINING NORTH OF THE REGION THROUGH MUCH OF THE NEXT WEEK. AT THE SURFACE...A PARENT LOW PUSHES THROUGH THE GREAT LAKES MONDAY AND INTO ONTARIO MONDAY NIGHT. THE ASSOCIATED WARM FRONT WILL BE APPROACHING THE LOCAL AREA MONDAY AND MOVING NORTH ACROSS THE AREA MONDAY NIGHT. ANOTHER PARENT LOW PASSES THROUGH THE GREAT LAKES INTO SOUTHEAST CANADA LATE IN THE WEEK. THE ASSOCIATED WARM FRONT DEVELOPS NORTH OF THE REGION WITH THE COLD FRONT APPROACHING THE LOCAL REGION LATE IN THE WEEK. 850MB TEMPS INCREASE ABOUT 8 TO 10 DEGREES C BY NEXT TUESDAY THROUGH NEXT THURSDAY COMPARED TO FORECAST VALUES ON SUNDAY. LIKEWISE...1000 TO 850 MB MIXING RATIOS INCREASE THROUGH THE COURSE OF LONG TERM...WITH FORECAST VALUES OF 10 TO 13 G/KG TUESDAY THROUGH THURSDAY TIMEFRAME. THESE PARAMETERS POINT TO A TRANSITION TO AN INCREASINGLY WARM AND HUMID AIR MASS DURING THE LONG TERM. THESE WILL FEED INSTABILITY DURING THE DAY THAT WILL LINGER INTO THE NIGHT DUE TO THE MOISTURE ADVECTION AS WELL. THIS WILL ALLOW FOR POP UP SHOWERS AND THUNDERSTORMS...MAINLY ACROSS THE INTERIOR THAT WILL WORK THEIR WAY SOUTHEAST LATE AFTERNOON INTO THE EARLY EVENING. IN ADDITION...BY MONDAY NIGHT INTO TUESDAY MORNING...IT WILL BE THE THIRD NIGHT OF ONSHORE FLOW. THIS WILL ALLOW FOR PATCHY FOG TO DEVELOP. THIS WILL CYCLE WILL LIKELY REPEAT THE FOLLOWING FEW NIGHTS THEREAFTER INTO DAYBREAK OF THE FOLLOWING MORNING. OVERALL...WARMER TEMPERATURES ACROSS THE INTERIOR AND NYC WITH UPPER 70S TO MID 80S FOR HIGHS. HIGHS WILL BE A FEW DEGREES COOLER TO THE EAST ESPECIALLY ALONG IMMEDIATE SHORELINES WITH ONSHORE FLOW. NIGHT TIME LOWS WILL INCREASE ESPECIALLY MONDAY NIGHT AND THE FOLLOWING NIGHTS THEREAFTER WITH VALUES MOSTLY IN THE 60S AS A PERSISTENT SOUTHERLY FLOW CONTINUES TO ENTRAIN WARM AND HUMID CONDITIONS. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
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A COLD FRONT ACROSS UPSTATE NY WILL TRACK THRU THE AREA THIS AFTN. HI PRES BUILDS IN FROM THE W ON SAT. VFR THROUGH THE TAF PERIOD. LOW PROB OF AN ISOLD SHRA THRU 21Z. WNW FLOW BECOMES NW AFT THE FROPA IN THE 20-23Z TIME PERIOD. SPEEDS AND GUST FREQUENCY DIMINISH OVERNIGHT. WINDS THEN BACK TO THE W AROUND 10KT ON SAT. STRONGER SW FLOW KJFK DUE TO SEA BREEZE INFLUENCE. ...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: TIMING OF THE FRONT AND RESULTANT WIND SHIFT MAY BE ADJUSTED SLIGHTLY AS THE FEATURE APPROACHES. KLGA FCSTER COMMENTS: TIMING OF THE FRONT AND RESULTANT WIND SHIFT MAY BE ADJUSTED SLIGHTLY AS THE FEATURE APPROACHES. KEWR FCSTER COMMENTS: TIMING OF THE FRONT AND RESULTANT WIND SHIFT MAY BE ADJUSTED SLIGHTLY AS THE FEATURE APPROACHES. KTEB FCSTER COMMENTS: TIMING OF THE FRONT AND RESULTANT WIND SHIFT MAY BE ADJUSTED SLIGHTLY AS THE FEATURE APPROACHES. KHPN FCSTER COMMENTS: TIMING OF THE FRONT AND RESULTANT WIND SHIFT MAY BE ADJUSTED SLIGHTLY AS THE FEATURE APPROACHES. KISP FCSTER COMMENTS: TIMING OF THE FRONT AND RESULTANT WIND SHIFT MAY BE ADJUSTED SLIGHTLY AS THE FEATURE APPROACHES. .OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY... .SAT...VFR. SW WINDS 10-15KT. .SUN...VFR. SW WINDS 10-20KT. .MON...VFR. SW WINDS 10-20KT. .TUE...MRNG MVFR OR LOWER POSSIBLE IN FOG/STRATUS. SW WINDS. .WED...POCKETS OF MVFR OR LOWER POSSIBLE IN FOG/STRATUS. SW WINDS.
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&& .MARINE... THE PRESSURE GRADIENT TIGHTENS THIS AFTERNOON WITH WIND GUSTS 25 TO 30 KT AHEAD OF A COLD FRONT...WITH STRONGEST WIND EXPECTED NEAR THE SHORE. A SMALL CRAFT ADVISORY IS IN EFFECT FOR ALL WATERS FROM THIS AFTERNOON THROUGH SATURDAY MORNING. WIND IS EXPECTED TO DIMINISH ON SATURDAY...WITH SUB SCA CONDITIONS. SUB SCA CONDITIONS WILL PREVAIL MUCH OF THE LONG TERM PERIOD ACROSS THE WATERS WITH OFFSHORE HIGH PRESSURE IN PLACE. WINDS AND SEAS INCREASE TUESDAY AND TUESDAY NIGHT IN RESPONSE TO A TIGHTENING PRESSURE GRADIENT BETWEEN PARENT LOW DEEPENING IN SOUTHEAST CANADA AND OFFSHORE HIGH PRESSURE. SCA IN THIS TIME PERIODS BECOMES MORE PROBABLE AS WIND GUSTS ARE FORECAST TO INCREASE TO 25 KT ACROSS OCEAN WATERS AND OCEAN SEAS INCREASE TO 5-6 FT. && .FIRE WEATHER... WEATHER CONDITIONS TODAY MAY BE CONDUCIVE TO GROWTH/SPREAD OF ANY FIRES THAT DEVELOP. RH VALUES ARE EXPECTED TO FALL THROUGH THE DAY TO NEAR 30 PERCENT...AND W-NW WINDS WILL GUST TO 25-30 MPH DURING THE AFTERNOON. WITH MARGINAL RH VALUES AND POSSIBILITY OF SOME RAIN SHOWERS...WILL HOLD OFF ON ANY RED FLAG HEADLINES. SATURDAY COULD ALSO BE A DAY OF CONCERN ESPECIALLY FOR NYC METRO...SOUTHERN CT AND LONG ISLAND...WITH MIN RH AGAIN IN THE 20S AND NW-W WINDS GUSTING TO 20-25 MPH. && .HYDROLOGY... NO SIGNIFICANT WIDESPREAD RAIN EXPECTED THROUGH THE FORECAST PERIOD. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT SATURDAY FOR ANZ330-335- 338-340-345-350-353-355. && $$ SYNOPSIS...FIG/JM NEAR TERM...BC/FIG SHORT TERM...FIG LONG TERM...JM AVIATION...JMC MARINE...FIG/JM FIRE WEATHER... HYDROLOGY...FIG/JM

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