Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 262336 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 736 PM EDT SUN JUL 26 2015 .SYNOPSIS... A WEAKENING COLD FRONT APPROACHES FROM THE WEST THIS EVENING AND DISSIPATES NEAR OR JUST WEST OF THE HUDSON RIVER LATE TONIGHT. A WEAK TROUGH WILL REMAIN ACROSS THE AREA ON MONDAY. HIGH PRESSURE WILL BUILD IN FOR THE MID WEEK...PASSING TO THE SOUTH. A COLD FRONT APPROACHES THURSDAY...CROSSING THE AREA THURSDAY AFTERNOON AND EVENING. WEAK HIGH PRESSURE BUILDS IN FRIDAY...THEN SLIDES OFFSHORE ON SATURDAY. A WEAK FRONTAL BOUNDARY APPROACHES SUNDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AN AXIS OF MDT-HIGH INSTABILITY WITH CAPES 1000-2000 J/KG AND AN APPROACHING WEAK COLD FRONT WILL RESULT IN SCT CONVECTION THROUGH THE NIGHT...PROGRESSING EAST FROM THE LOWER HUDSON VALLEY AND NE NJ AFTER DARK. A LACK OF DEEP-LAYERED SHEAR SUPPORTS SHORT SHORT-LIVED CELLS WITH THE POTENTIAL FOR BRIEF HEAVY RAINFALL... SMALL HAIL...AND GUSTY WINDS. A PULSE SEVERE THUNDERSTORM IS NOT OUT OF THE QUESTION...ESPECIALLY EARLY THIS EVENING NORTH AND WEST OF THE NYC METRO WHERE THE GREATEST INSTABILITY EXIST. A MODERATE SLY FLOW WILL GUST UP TO 20 MPH THIS EVENING BEFORE THE COASTAL JET WEAKENS. LOWS WILL RANGE FROM THE MID 60S INLAND TO AROUND 70 AT THE COAST. DEW POINTS WILL BE WELL INTO THE 60S MAKING IT QUITE HUMID AS WELL. THERE IS A HIGH RISK FOR THE METEOROLOGICAL ENHANCEMENT OF RIP CURRENT FORMATION AT ATLANTIC BEACHES THROUGH THIS EVENING. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... A MID LEVEL SHORT WAVE TROF EXITS OFF THE COAST IN THE LATE MORNING/EARLY AFTERNOON HOURS WITH SHORT WAVE RIDGING TO FOLLOW. THIS COULD PUT A LID ON THE CONVECTION FOR THE REMAINDER OF MON. A THERMAL TROF ACROSS THE AREA WITH MDT-HIGH INSTABILITY...BUT ONCE AGAIN WEAK SHEAR...WILL RESULT IN SCT CONVECTION FOR THE FIRST HALF OF THE DAY...WHICH THEN DISSIPATES BY EVE. HIGH PRESSURE BUILDS EAST FROM THE OHIO VALLEY MON NIGHT. PREFERENCE WAS TO GO WITH MET MOS HIGHS ON MON...WHICH ARE WARMER...IN THE MID TO UPPER 80S. THE GFS APPEARS TOO WET AND THUS THE COOLER TEMPS. MON NIGHT WILL BE ANOTHER WARM MUGGY NIGHT WITH LOWS IN THE MID 60S TO THE LOWER 70S. THERE IS A MODERATE RISK FOR THE METEOROLOGICAL ENHANCEMENT OF RIP CURRENT FORMATION AT ATLANTIC BEACHES MONDAY. && .LONG TERM /TUESDAY THROUGH SUNDAY/... ON TUESDAY...UPPER TROUGH SLOWLY DEPARTS TO THE EAST AS LARGE RIDGE BUILDS. 12Z MODEL SUITE SHOWS PVA MOVING ACROSS THE NORTHEAST FROM NW TO SE THROUGH THE DAY TUESDAY...WITH LINGERING SFC TROUGH NEARBY. THIS VORT PLACEMENT DOES DIFFER SOMEWHAT PER MODEL...BUT CANNOT RULE OUT A STRAY SHOWER OR TSTM EASTERN ZONES DURING THE DAY TUESDAY AS ANY LIFT IN CONJUNCTION WITH WEAK INSTABILITY COULD TRIGGER SOMETHING. BEST COVERAGE THOUGH WILL BE OVER NEW ENGLAND. THEN AS RIDGE BUILDS AND SUBSIDENCE ENSUES...DRY WEATHER CAN BE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. UPPER LEVEL RIDGE EVENTUALLY SETTLES ACROSS THE SOUTHERN STATES...AS THE WESTERLIES BEGIN TO SAG ACROSS THE GREAT LAKES STATES...WITH LOWERING HEIGHTS FORECAST OVER THE NORTHEAST THURSDAY. THIS WILL RESULT IN A WEAKENING COLD FRONT THAT IS PROGGED TO MOVE THROUGH SOMETIME LATE THURSDAY. IT DOES APPEAR THAT THIS FRONT WILL PASS FAR ENOUGH TO THE EAST DURING THE LATTER PORTION OF THE WEEK. AS SUCH...HIGH PRESSURE BUILDS IN. NEXT WEAK FRONTAL BOUNDARY APPROACHES SUNDAY AS WEAK TROUGH SETTLES ACROSS THE NORTHERN AND NORTHEASTERN STATES ALOFT. AS FOR SENSIBLE WEATHER WED THROUGH SUNDAY...BEST CHANCE FOR CONVECTION CONTINUES TO BE LATER THURSDAY AHEAD OF THE FRONT. ANY LIFT ALOFT IS WEAK...BUT MARGINAL TO PERHAPS MODERATE CAPE WILL BE AVAILABLE POTENTIALLY...AND A SLIGHTLY COOLER AND DRIER AIRMASS MOVING EAST INTO THE HOT AND HUMID AIR MAY BE ENOUGH TO PRODUCE A FEW SHOWERS AND TSTMS. DRY FRIDAY THROUGH SUNDAY...ALTHOUGH A FEW STRAY SHOWERS AND TSTMS CANNOT BE RULED OUT SUNDAY AHEAD OF THE TROUGH. TEMPS BEGIN TO WARM TUESDAY...WITH A MOS BLEND USED FOR FCST HIGH/S. EXPECT READINGS IN THE 80S...APPROACHING OR TOUCHING 90 IN AND AROUND NYC METRO. DEW POINTS MAY MIX OUT SOMEWHAT PER MOS AND POSSIBLE WEST TO SW FLOW. AS SUCH...HEAT INDICES MAY FALL SHORT OF THE MID 90S IN AND AROUND NYC. ON WEDNESDAY...THE HEAT BUILDS WITH 90S EXPECTED ACROSS THE CWA AFTER A VERY WARM START TO THE DAY. MORNING LOWS WILL BE IN THE 70S...EXCEPT SOME 60S ACROSS THE INTERIOR. HEAT INDICES LIKELY REACH THE MID TO UPPER 90S. TEMPS REMAIN QUITE WARM TO HOT THROUGH THURSDAY...WITH 70S AT NIGHT AND UPPER 80S TO LOWER 90S DURING THE DAY. A SLIGHT COOL DOWN BEHIND THE FRONT IS EXPECTED THURSDAY NIGHT THROUGH SUNDAY...BUT IT WILL REMAIN QUITE WARM TO HOT WITH TEMPS AVERAGING ABOVE NORMAL BY ABOUT 5 DEGREES. USED A WPC AND GRIDDED MOS BLEND. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... LOW CONFIDENCE FORECAST TONIGHT THROUGH MONDAY AS A WEAKENING COLD FRONT MOVES ACROSS THE LOCAL AIRSPACE TONIGHT...AND THEN DISSIPATES JUST SOUTH OF LONG ISLAND MONDAY MORNING. SCATTERED SHRA/TSRA LIKELY AT SOME POINT LATE TONIGHT THROUGH MONDAY MORNING. CURRENT THINKING HAS BEST TIMING FROM 07-11Z NORTH AND WEST OF KNYC TERMINALS...AND FROM 08-12Z FOR KJFK/KLGA. BASED ON LATEST SHORT RANGE GUIDANCE...DO NOT THINK STORMS WILL HOLD TOGETHER BEFORE REACHING KBDR/KISP/KGON AT THIS TIME...AND WILL NOT MENTION IN TAFS. FOR THE REST OF THE TAFS...WILL USE TEMPO GROUPS TO CONVEY TIMING OF CONVECTION. THERE ARE STRONG TSRA WEST OF KSWF...AND SOME OF THOSE STORMS COULD IMPACT KSWF EARLY THIS EVENING. WILL TEMPO FROM 00-04Z...BUT VCTS MAY BE A BETTER DESCRIPTION OF WHAT WILL HAPPEN THERE. S/SW WINDS WILL DIMINISH TO 5 KT OR LESS THIS EVENING...AND THEN SOUTH WINDS WILL INCREASE TO 5-10 KT LATE MONDAY MORNING WITH LOCALLY STRONGER WINDS AT COASTAL TERMINALS DUE TO AFTERNOON SEA BREEZES. .OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY... .MONDAY NIGHT...VFR. .TUESDAY-THURSDAY...MAINLY VFR. 5-6SM HAZE DEVELOPMENT POSSIBLE. SW WINDS WITH AFTERNOON SEABREEZE DEVELOPMENT AT COASTAL TERMINALS. THUNDER IS POSSIBLE THURSDAY AFTERNOON. .FRIDAY...VFR. && .MARINE... WIND AND SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT LEVELS THROUGH TONIGHT. MARGINAL SCA GUSTS POSSIBLE ACROSS WESTERN OCEAN WATERS AND SURROUNDING NEARSHORE WATERS THROUGH THIS EVE WITH COASTAL JET. OCEAN SEAS LIKELY BUILD TO AROUND 4 FT BY THIS EVENING. SUB SCA CONDITIONS WITH A FAIRLY WEAK PRESSURE GRADIENT MON INTO MON NIGHT. A WEAK TROUGH TUESDAY MOVES EAST AS HIGH PRESSURE BUILDS WEDNESDAY. WINDS AND THUS SEAS SHOULD REMAIN FAIRLY TRANQUIL DURING THIS TIME. THE PRESSURE GRADIENT TIGHTENS SOMEWHAT THURSDAY AHEAD OF A WEAKENING COLD FRONT. WINDS INCREASE...BUT SHOULD REMAIN BELOW SCA THRESHOLDS. HOWEVER...OCEAN SEAS LIKELY BUILD CLOSE TO 5 FEET. WAVE WATCH REMAINS CONSISTENT IN FORECASTING THIS...BUT IT COULD BE OVERDONE BY A FOOT OR SO. WINDS DIMINISH BEHIND THE SLOW MOVING FRONT AS THE PRESSURE GRADIENT WEAKENS. SEAS WILL SUBSIDE AS A RESULT. && .HYDROLOGY... NO WIDESPREAD SIGNIFICANT PRECIPITATION IS EXPECTED INTO THE MIDDLE OF THE WEEK. HOWEVER...ANY STRONGER STORMS THAT DUE HAPPEN TO FORM ON MONDAY WILL BE VERY SLOW TO MOVE...WITH STORM MOTION FORECAST TO BE 10 KT OR LESS. AS A RESULT...THERE IS THE POTENTIAL FOR LOCALIZED URBAN/POOR DRAINAGE FLOODING FROM MONDAY INTO MONDAY EVENING. THERE IS ALSO THE POSSIBILITY FOR LOCALLY HEAVY RAINFALL WITH ANY STRONGER STORMS THURSDAY AFTERNOON/EVENING...WHICH COULD ALSO POSSIBLY CAUSE LOCAL URBAN/POOR DRAINAGE FLOODING. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...HIGH RIP CURRENT RISK UNTIL 9 PM EDT THIS EVENING FOR NYZ075- 080-081-178-179. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...DW/PW NEAR TERM...DW SHORT TERM...DW LONG TERM...PW AVIATION...MPS MARINE...DW/PW HYDROLOGY...DW/PW

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