Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 091951 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 351 PM EDT WED JUL 9 2014 .SYNOPSIS... A COLD FRONT SWINGS THROUGH THE REGION TONIGHT...STALLING JUST TO THE SOUTH ON THURSDAY. HIGH PRESSURE WILL BUILD OVER THE AREA FOR THE FIRST HALF OF THE WEEKEND...THEN SLIDE OFFSHORE THROUGH THE BEGINNING OF NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... MAIN CONCERN FOR THE LATE AFTN THROUGH THIS EVENING WILL BE THE DEVELOPMENT OF ISO-SCT STRONG-SVR TSTMS OUT AHEAD OF AN APPROACHING COLD FRONT. INITIAL DEVELOPMENT ALREADY OCCURRING LATE THIS AFTN ALONG PRE FRONTAL TROUGH AND ASSOCIATED WITH PASSING VORT MAX. THOUGH NOT AS IMPRESSIVE AS PREVIOUS DAYS...STILL SEEING SBCAPE VALUES PUSHING 1000 J/KG OVER INTERIOR REGIONS WHILE STRONGER SHEAR VALUES BETWEEN 35-45 KTS CONTINUE. HOWEVER...OVERALL EXPECTING BETTER DYNAMICAL FORCING WITH A STRONGER FRONTAL BOUNDARY AT THE SFC AND THE PASSING SHORTWAVES ALOFT. COVERAGE WILL INCREASE INTO THIS EVENING AS THE COLD FRONT NEARS...THOUGH NOT EXPECTING MORE THAN SCT COVERAGE OVER INTERIOR REGIONS. MAIN THREATS ASSOCIATED WITH THE STORMS WILL BE GUSTY- DAMAGING WINDS...WITH POSSIBLE HAIL. ONSHORE FLOW TODAY KEEPING A MORE STABLE AIRMASS IN PLACE AT THE COAST...SO EXPECTING MINIMAL STRONG-SVR THREAT AND EVEN COVERAGE. COLD FRONT FINALLY REACHES THE AREA AFTR 00Z...THEN PROGRESSES THROUGH TONIGHT...EVENTUALLY STALLING JUST SOUTH OF LONG ISLAND BY 12Z THURS MORNING. WILL CONTINUE TO MENTION THE SLIGHT CHC POTENTIAL FOR PCPN RIGHT ALONG THE FRONT. WEAK LOW PRESSURE FORMS ALONG THE FRONT LATE TONIGHT...WITH THE MESO MODELS IN GOOD AGREEMENT OF PCPN THEN MOVING TO THE NORTH FROM THE DELMARVA REGION. HOWEVER...THE CONFIDENCE OF IT REACHING LONG ISLAND/NYC METRO ON THE LOWER END AND WILL JUST HAVE CHC POPS OVER THE OCEAN WATERS. COOLER AIR WILL BE SLOW TO MOVE IN...SO WILL HAVE ONE MORE NIGHT OF SLIGHTLY ABOVE NORMAL TEMPS. SIDED MORE WITH A MET SOLUTION FOR TEMP/DEW PT. THERE IS A HIGH RISK FOR RIP CURRENT DEVELOPMENT ON ALL ATLANTIC OCEAN BEACHES THROUGH THIS EVENING. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... AS THE MODELS HAVE BEEN SHOWING FOR THE PAST COUPLE OF DAYS...COLD FRONT PUSHES SOUTH AND REMAINS STALLED JUST SOUTH OF LONG ISLAND. MULTIPLE WEAK LOWS RIDE THE FRONT TOMORROW INTO TOMORROW NIGHT. OVERALL...EXPECTING DRIER AIR TO MOVE IN. BUT THERE MIGHT BE JUST ENOUGH MOISTURE LEFT IN THE ATMO COMBINING WITH DECENT FORCING ASSOCIATED WITH THE FRONT IN THE VICINITY AT THE SFC AND PASSING SHORTWAVES ROUNDING THE BASE OF THE UPPER LVL TROUGH TO GENERATE AN ISO SHOWER OR EVEN TSTM IN THE AFTN. WILL KEEP SLIGHT CHC WORDING IN FOR NOW DURING THE PERIOD...WITH A GOOD CHC OF MOST OF THE REGION REMAINING DRY THOUGH. TEMPS FINALLY DROP DOWN TO NEAR NORMAL...USING A GENERAL BLEND OF MET/MAV GUIDANCE. THERE IS A MODERATE RISK OF RIP CURRENT DEVELOPMENT ALONG ALL OF THE ATLANTIC OCEAN BEACHES. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... MODEL CONSENSUS IS THAT THE FRONT WILL BE OFFSHORE BY FRI MRNG...WITH DRY WX ACROSS THE CWA. THERE WILL BE PCPN GENERATED ALONG THE FRONT...AND THE PROGS ARE FAIRLY CLOSE TO THE SHORE...SO THE EXACT SPEED WILL NEED TO BE WATCHED AS ANY SLOWDOWN COULD RESULT IN RAIN AT LEAST FRI MRNG. HIPRES THEN BUILD INTO THE REGION LATE FRI THRU SAT. ALTHOUGH THE GFS AND ECMWF SUGGEST SOME ISOLD SHRA/TSTMS SAT ALONG THE CWA PERIPHERY...HAVE SIDED CLOSER TO THE NAM WHICH KEEPS THE CONVECTIVELY FAVORABLE INSTABILITY FURTHER W. THE SHORES WILL BE DRY REGARDLESS...WITH THE MAIN UNCERTAINTY ACROSS THE WRN INTERIOR. THE HIGH DRIFTS OFFSHORE SUN AND SETTLES OVER THE ATLANTIC THRU THE BEGINNING OF NEXT WEEK. AFTN AND EVE TSTMS POSSIBLE ON SUN...ESPECIALLY INTERIOR...AS RETURN FLOW INCREASES MOISTURE AND INSTABILITY. A STRONG CLOSED H5 LOW THEN DROPS INTO THE UPR GREAT LAKES MON AND TUE. SINGLE DIGIT H85 TEMPS WITH THIS ACROSS NRN MN INTO THE UP. THE SW FLOW AHEAD OF THE LOW WILL PUMP WARM HUMID AIR INTO THE REGION FOR MON AND TUE. THIS SETUP WILL HAVE THE POTENTIAL TO PRODUCE A SVR OUTBREAK AT SOME POINT MON-TUE. && .AVIATION /20Z WEDNESDAY THROUGH MONDAY/... COLD FRONT CONTINUES TO WORK ITS WAY INTO THE REGION FROM THE WEST...AND WILL MOVE ACROSS THE TERMINALS AFTER MIDNIGHT TONIGHT. TSTMS DEVELOPING TO THE WEST. KSWF WILL BE MOST IMPACTED THROUGH 00Z...AND THEN MAIN TIMING FOR TSTMS AT KJFK/KLGA/KEWR/KTEB/KSWF/KHPN WILL BE FROM 00-06Z THURSDAY. DUE TO THE SCATTERED NATURE OF THE CONVECTION...WILL LEAVE OUT OF TAFS FOR NOW...AND WILL SEND AMDS TO THE TAFS AS STORMS DEVELOP AND CAN PINPOINT IMPACTS TO TERMINALS. OTHERWISE...MAINLY VFR. SW FLOW...TURNING S AT COASTAL TERMINALS BEHIND THE SEA BREEZE. WINDS MAINLY 10-15 KT THROUGH THIS EVENING. WINDS BECOME SW 4-8 KT THIS EVENING. AFTER COLD FRONT MOVES ACROSS THE TERMINALS...WINDS SHIFT TO THE N. ...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: MODERATE CONFIDENCE ON WINDS. LOW CONFIDENCE ON CONVECTION. AMDS LIKELY THROUGH THIS EVENING FOR DEVELOPMENT OF TSTMS. KLGA FCSTER COMMENTS: MODERATE CONFIDENCE ON WINDS. LOW CONFIDENCE ON CONVECTION. AMDS LIKELY THROUGH THIS EVENING FOR DEVELOPMENT OF TSTMS. KEWR FCSTER COMMENTS: MODERATE CONFIDENCE ON WINDS. LOW CONFIDENCE ON CONVECTION. AMDS LIKELY THROUGH THIS EVENING FOR DEVELOPMENT OF TSTMS. KTEB FCSTER COMMENTS: MODERATE CONFIDENCE ON WINDS. LOW CONFIDENCE ON CONVECTION. AMDS LIKELY THROUGH THIS EVENING FOR DEVELOPMENT OF TSTMS. KHPN FCSTER COMMENTS: MODERATE CONFIDENCE ON WINDS. LOW CONFIDENCE ON CONVECTION. AMDS LIKELY THROUGH THIS EVENING FOR DEVELOPMENT OF TSTMS. KISP FCSTER COMMENTS: MODERATE CONFIDENCE ON WINDS. .OUTLOOK FOR 20Z THURSDAY THROUGH MONDAY... .THURSDAY-SATURDAY...MAINLY VFR. .SUNDAY-MONDAY...SHOWERS AND TSTMS POSSIBLE. && .MARINE... SCA REMAINS IN EFFECT FOR THE OCEAN WATERS FOR SEAS 4-6 FT. WESTERN OCEAN WATERS EXPECTED TO BEGIN SUBSIDING BY THIS EVENING AS THE FRONT NEARS...WITH THE REMAINING WATERS SUBSIDING LESS THAN 5 FT BY TOMORROW AFTN. WINDS SHOULD REMAIN SUB-SCA THROUGH THURSDAY NIGHT. WINDS AND SEAS ARE PROGGED TO REMAIN BLW SCA LVLS FRI-SUN. SCA CONDITIONS RETURN MON AND TUE AS STRONG SW FLOW DEVELOPS. && .HYDROLOGY... NO WIDESPREAD SIGNIFICANT HYDROLOGIC ISSUES EXPECTED THROUGH THE WEEKEND. ANY TSTMS MON AND TUE WILL BE CAPABLE OF PRODUCING LOCALLY HVY RAIN. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ355. SMALL CRAFT ADVISORY UNTIL 2 PM EDT THURSDAY FOR ANZ350. SMALL CRAFT ADVISORY UNTIL 9 AM EDT THURSDAY FOR ANZ353. && $$ SYNOPSIS...JMC/SEARS NEAR TERM...SEARS SHORT TERM...SEARS LONG TERM...JMC AVIATION...MPS MARINE...JMC/SEARS HYDROLOGY...JMC/SEARS

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