Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 292040 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 440 PM EDT MON JUN 29 2015 .SYNOPSIS... AS LOW PRESSURE MOVES INTO THE CANADIAN MARITIMES THROUGH TONIGHT...HIGH PRESSURE WILL BUILD INTO THE NORTHEAST. ANOTHER LOW WILL MOVE THROUGH THE EASTERN GREAT LAKES ON TUESDAY WITH ITS WARM FRONT APPROACHING FROM THE SOUTH. IT MOVES THROUGH WEDNESDAY. AS A COLD FRONT MOVES SLOWLY SOUTHEAST ACROSS THE REGION WEDNESDAY NIGHT...IT WILL BECOME NEARLY STATIONARY SOUTH OF THE AREA THURSDAY THROUGH MONDAY AS A SERIES OF LOW PRESSURE SYSTEMS MOVE EAST ALONG THE FRONT. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... THE RIDGING CONTINUES AT MID TO UPPER LEVELS TONIGHT AS UPPER LEVEL SOUTHWESTERLY JET STREAK EXITS NORTHEAST OF REGION. AS A LOW MOVES FARTHER INTO THE CANADIAN MARITIMES...HIGH PRESSURE WILL BUILD IN FROM THE EAST AT THE SURFACE. A RESULTING DECREASE IN CLOUDS CAN BE EXPECTED. WINDS WILL BECOME LIGHTER AS THE NIGHT PROGRESSES...AND WITH THE DECREASING CLOUDS...RADIATIONAL COOLING WILL ALLOW FOR RELATIVELY COOLER TEMPS IN THE INTERIOR AND RURAL SECTIONS OF THE REGION. LOWS WERE 2/3 ECS AND 1/3 GMOS...WITH A RANGE FROM THE MID 50S TO UPPER 60S. THE HIGH RISK OF RIP CURRENTS AT OCEAN BEACHES CONTINUES INTO THIS EVENING. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY/... THE HIGH PRESSURE WILL STILL BE PREVALENT TUESDAY WITH THE RIDGE OFFSHORE. CLOUDS WILL INCREASE FROM THE WEST DURING THE DAY WITH AN INCREASING CHANCE OF SHOWERS MAINLY WEST OF NYC TOWARDS THE LATTER PORTION OF THE DAY. MORE SUN EXPECTED FARTHER EAST THAN THE PREVIOUS DAY AND DESPITE A SE FLOW...TEMPS ALOFT AT 850MB WARM A FEW DEGREES COMPARED TO THE PREVIOUS DAY AS WELL. AS A RESULT...HIGH TEMPS WILL BE A FEW DEGREES WARMER AS WELL. HIGHS RANGE FROM THE LOW TO MID 80S. FOR TUESDAY NIGHT AND WEDNESDAY...A LOW WILL BE DEVELOPING IN THE OHIO VALLEY INTO THE EASTERN GREAT LAKES. ITS ASSOCIATED WARM FRONT WILL BE APPROACHING FROM THE SOUTHWEST. IT WILL MAKE SLOW PROGRESS AND NOT MOVE THROUGH UNTIL DURING THE DAY WEDNESDAY. THE CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS BECOMES MORE WIDESPREAD TUESDAY NIGHT. INSTABILITY AT THE SURFACE INCREASES LATE TUESDAY NIGHT AND WEDNESDAY...MAKING FOR A RELATIVELY HIGHER CHANCE OF THUNDERSTORMS. SHOWERS WILL BE LIKELY LATE TUESDAY NIGHT AND WEDNESDAY WITH SCATTERED EMBEDDED THUNDERSTORMS FROM TIME TO TIME. MORE OF SYNOPTIC FORCING CONVEYED BY MODELS WITH SHARPENING SHORTWAVE EARLY WEDNESDAY TRAVERSING THE REGION AND ASSOCIATED UPPER LEVEL SOUTHERLY JET STREAK. THIS WILL HELP ADVECT IN GREATER MOISTURE WITH MORE SOUTHERLY FLOW THROUGH THE ATMOSPHERE. LOWS TUESDAY NIGHT CONVEYED THE WARMER SIDE OF GUIDANCE WITH VALUES RANGING FROM THE LOW TO UPPER 60S. TOOK COOLER SIDE OF GUIDANCE FOR HIGHS WEDNESDAY WITH A RANGE FROM THE UPPER 70S TO LOWER 80S. THERE WILL BE A MODERATE RISK OF RIP CURRENTS AT OCEAN BEACHES ON TUESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... FORECAST UNCERTAINTY REGARDING TIMING AND LOCATION OF RAIN WILL REMAIN HIGH LEADING TO A LOW CONFIDENCE LONG TERM FORECAST. WHAT WE KNOW...MEAN POSITIONS OF THE UPPER LVL RIDGE ACROSS THE WESTERN U.S. AND EASTERN U.S. WILL NOT CHANGE MUCH. SHORT WAVES WILL CONTINUE TO DEVELOP AND ROTATE AROUND THE POLAR VORTEX JUST NORTH OF HUDSON BAY CANADA. AS EACH SHORT WAVE DROPS FAR ENOUGH SE...IT WILL BRING INCREASES CHANCES OF SHOWERS AND TSTMS. WHAT WE DONT KNOW...THE SPECIFIC TRACKS...INTENSITY AND TIMING OF THE APPROACHING SHORT WAVES. WED NIGHT...WX CONDITIONS ARE FCST TO IMPROVE WITH THE SLOW PASSAGE OF A COLD FRONT MVG SE ACROSS THE REGION...BRINGING A TEMPORARY END TO A ROUND OF SHOWERS AND TSTMS. THU THROUGH THU NIGHT...THIS FCST DEPENDS ON HOW FAR SOUTH THE FRONT MAKES IT AS A WAVE OF LOW PRES DEVELOPS ALONG IT AND MVS EAST. INCLUDED A CHC OF TSTMS MAINLY THU AFTN AND EVE WITH THE APPROACH OF THIS LOW AND AN UPPER LVL SHORT WAVE. FRI...POTENTIAL FOR A FAIR WX DAY AS SUBSIDENCE BEHIND THE EXITING LOW ALONG WITH HIGH PRES TO THE NORTH MAY HOLD MOST SHOWERS SOUTH AND WEST OF THE REGION. SAT...INCREASING CHC FOR SHOWERS AND TSTMS WITH THE APPROACH OF THE NEXT LOW WITH MAX CHANCES DURG THE AFTN AND EVE. SUNDAY...POTENTIAL FOR A FAIR WX DAY AS SUBSIDENCE BEHIND THE EXITING LOW PASSES ACROSS THE REGION. && .AVIATION /21Z MONDAY THROUGH SATURDAY/...
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HIGH PRESSURE BUILDS TONIGHT...FOLLOWED BY LOW PRESSURE AND AN APPROACHING WARM FRONT TUESDAY. VFR THROUGH THE TAF PERIOD. ANY CU SCATTERS BY EVENING. MID AND HIGH CLOUDS INCREASE LATE TONIGHT AND TUESDAY. W/SW WIND FLOW LIGHTENS AS IT BACKS TO THE SW. LOCAL SEA BREEZES ARE OCCURRING AT KISP...KBDR AND KGON. THE SEA BREEZE HAS BEEN PUSHED SOUTH OF KJFK AND MAY NOT FULLY MOVE THROUGH UNTIL AROUND 00Z. WINDS LIGHTEN TONIGHT. THEN S/SE WINDS INCREASE TUE MORNING. ...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: SEABREEZE HOLDS OFF UNTIL CLOSER TO THE 00Z-01Z TIME FRAME. AMENDMENTS ARE POSSIBLE FOR UPDATES TO TIMING. KLGA FCSTER COMMENTS: AMENDMENTS FOR POSSIBLE LATE DAY SEA BREEZE. KEWR FCSTER COMMENTS: W/SW WINDS CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON. NOT EXPECTING A SEA BREEZE. KTEB FCSTER COMMENTS: WEST WINDS SHOULD BACK SLIGHTLY TO THE W/SW FOR THE REMAINDER OF THE AFTERNOON. KHPN FCSTER COMMENTS: WEST WINDS SHOULD BACK SLIGHTLY TO THE W/SW FOR THE REMAINDER OF THE AFTERNOON. KISP FCSTER COMMENTS: NO UNSCHEDULED AMDS EXPECTED. .OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY... .TUESDAY AFTERNOON...VFR. CHANCE OF TSRA...MAINLY WEST OF NYC TERMINALS. .TUESDAY NIGHT-SATURDAY...SUB VFR POSSIBLE AT TIMES THROUGH THE PERIOD IN SHRA AND POSSIBLE TSRA.
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&& .MARINE... WINDS WILL BE TRENDING DOWNWARD TONIGHT. GUSTS TO 25 KT STILL EXPECTED ACROSS OCEAN MAINLY EAST OF FIRE ISLAND INLET INTO THE EVENING. THE GUSTS DROP OFF AFTER MIDNIGHT. OCEAN SEAS WILL STAY ELEVATED NEAR 5-6 FT BECAUSE OF LINGERING EASTERLY SWELL. SCA EXTENDED TO 2AM TUE FOR FIRE ISLAND TO MORICHES INLET AND TO 6AM TUE FOR MORICHES TO MONTAUK. SUB SCA CONDITIONS WITH A WEAK PRESSURE GRADIENT EXPECTED TUE INTO WED. NON OCEAN WATERS STAY BELOW SCA. WED NIGHT THRU THU MORNING...SEAS WILL GRADUALLY SUBSIDE BELOW SMALL CRAFT ADVISORY LVLS OF 5 FT BY THU AFTN. THU AFTN THRU SATURDAY...CHANCE OF TSTMS MAINLY DURING THU AND SAT AFTN AND EVENINGS WITH THE APPROACH OF LOW PRES SYSTEMS MOVING EAST ALONG A NEARLY STATIONARY FRONT JUST SOUTH OF THE COASTAL WATERS. WINDS AND SEAS ARE FORECAST TO REMAIN BELOW SMALL CRAFT ADVISORY LVLS OUTSIDE OF TSTMS. && .HYDROLOGY... NO WIDESPREAD SIGNIFICANT RAINFALL IS EXPECTED THROUGH TUE. TUE NIGHT THROUGH WED AFTN...PW VALUES 1.5 TO 1.75 INCHES WILL ENABLE ANY SHOWERS OR THUNDERSTORMS TO PRODUCE LOCALLY HEAVY RAIN. THE FORECAST BASIN AVG OF RAIN IS AROUND A HALF INCH BUT RAIN AMOUNTS COULD BE HIGHER LOCALLY UP TO 1 INCH APPROXIMATELY...POSSIBLY HIGHER. THIS COULD CAUSE AT LEAST MINOR URBAN/POOR DRAINAGE FLOODING...AND GIVEN EXPECTED ANTECEDENT CONDITIONS...POSSIBLY LOCALIZED FLASH FLOODING. THU AFTN THRU EVE AND SAT AFTN THRU EVE...AS LOW PRES SYSTEMS MOVE EAST ALONG A COLD FRONT...THERE IS A CHC OF 1/2-3/4- INCH RAIN WITH ISOLATED HIGHER AMOUNTS ASSOCIATED WITH HEAVIER SHOWERS AND TSTMS. MINOR URBAN FLOODING IS POSSIBLE. THERE IS A LOW PROB OF FLASH FLOODING. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR ANZ350. SMALL CRAFT ADVISORY UNTIL 2 AM EDT TUESDAY FOR ANZ353. && $$ SYNOPSIS...GC/JM NEAR TERM...JM SHORT TERM...JM LONG TERM...GC AVIATION...DS/PW MARINE...GC/JM HYDROLOGY...GC/JM

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