Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KOKX 060639 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 239 AM EDT MON JUL 6 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD OVER THE ATLANTIC THROUGH THE BEGINNING OF THE WEEK. A COLD FRONT WILL THEN MOVE THROUGH WEDNESDAY INTO WEDNESDAY NIGHT...THEN STALL JUST TO THE SOUTH ON THURSDAY WITH WEAK WAVES OF LOW PRESSURE MOVING ALONG IT. HIGH PRESSURE SHOULD START TO BUILD BACK IN FRIDAY AND LAST THROUGH THE WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... LOW PRESSURE IN THE MID-ATLANTIC INCREASING CLOUDS ACROSS THE AREA WITH ONSHORE FLOW ALONG THE COAST. THEREFORE...SLIGHTLY ADJUSTED UP WITH TEMPERATURES FOR PORTIONS OF THE REGION. THE CLOUDS ARE MOSTLY CIRRUS OUTFLOW FROM THE SOUTH AND WEST SO THERE WILL STILL BE SOME RADIATIONAL COOLING. HI PRES WILL BRING LGT WIND FLOW ACROSS THE REGION TNGT...ALLOWING FOR SOME PATCHY FOG DEVELOPMENT LATE. A BLEND OF THE GUIDANCE WAS USED FOR TEMPS. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/... THE SPRAWLING HI SETS UP OFFSHORE THRU THE PERIOD...RESULTING IN STEADY ONSHORE FLOW. DEWPOINTS WILL RESPOND BY RISING TO NEAR 70 BY TUE MRNG. ALTHOUGH SOME SFC BASED INSTABILITY DEVELOPS DURING THE DAY...SUBSIDENCE AND AN INCREASINGLY STABLE MARINE LAYER SHOULD SERVE TO INHIBIT CONVECTION. LEFT THE FCST DRY AS A RESULT. INCREASING THETA-E MAY SUPPORT AN ISOLD SHOWER OR TSTM MON NGT HOWEVER...PARTICULARLY WRN ZONES. LIFT SUPPLIED BY A RELATIVELY WEAK 25-30KT LLJ. FOG POSSIBLE WITH THE RISING HUMIDITY...ALTHOUGH THE INCREASING MID LVL MOISTURE MAY LIMIT DEVELOPMENT. AS A RESULT MAINTAINED ONLY PATCHY FOR NOW. TEMPS A BLEND OF THE GUIDANCE WHICH WAS IN GOOD AGREEMENT. THERE IS A MODERATE RISK FOR RIP CURRENT DEVELOPMENT MON AT THE ATLC BEACHES. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... A TROUGH OF LOW PRESSURE SHIFTS INVOF THE WESTERN ZONES TUESDAY AND REMAINS THERE THROUGH THE NIGHT. CHC OF SHOWERS AND TSTMS TUESDAY WITH INCREASING INSTABILITY AND MOISTURE CONVERGENCE. BETTER CHANCES WILL BE GENERALLY OVER THE NW HALF OF THE CWA. MAV/NAM MOS FOR HIGH TEMPS WERE SIMILAR AND A BLEND WAS USED...BUT THEY STILL MIGHT BE A COUPLE OF DEGREES TOO LOW...ESPECIALLY IF FEWER CLOUDS MATERIALIZE THAN FORECAST. A COLD FRONT THEN MOVES IN FROM THE NW WEDNESDAY AFTERNOON AND PROBABLY CLEARS THE EASTERN ZONES BY MIDNIGHT. WILL CAP POPS AT HIGH END CHC WEDS/WEDS NIGHT AS NAM AND CMC IMPLY CHC COVERAGE AT BEST...BUT WILL AT LEAST GO WITH SCT WORDING. POPS FOR THIS PERIOD MIGHT EVENTUALLY NEED TO BE BUMPED UP SHOULD NAM AND CMC COME INTO BETTER AGREEMENT WITH THE WETTER GFS AND ECMWF. ENOUGH CAPE IS PRESENT FOR A CHANCE OF THUNDERSTORMS...AND WITH HIGH PRECIPITABLE WATER VALUES...FAIRLY LIGHT STEERING FLOW...AND THE COLD FRONT BECOMING MORE ALIGNED WITH THIS STEERING FLOW ALOFT...THERE A CONCERN FOR HEAVY RAIN AND TRAINING OF CELLS STORMS THAT COULD LEAD TO LEAST MINOR URBAN/SMALL STREAM FLOODING. HIGHER CONFIDENCE NOW THAT THE COLD FRONT WILL STALL SOUTH OF THE CWA ON THURSDAY...BUT NOT BY MUCH. A WEAK WAVE OF LOW PRESSURE THEN TRAVELS WEST ALONG THIS BOUNDARY. TIMING OF ITS PASSAGE TO OUR SOUTH STILL A LITTLE UNCERTAIN...BUT IT`S TRENDING TOWARDS FRIDAY MORNING. WILL STILL LEAVE IN SLIGHT CHC POPS FOR THURSDAY BETWEEN THE UNCERTAINTY OF THIS TIMING AND TO ACCOUNT FOR ANY CHANCE THAT THE STALLED BOUNDARY ENDS UP FARTHER NORTH THAN CURRENTLY PROGGED. BUT RIGHT NOW THURSDAY WOULD SHAPE UP TO BE A DRY DAY. WILL THEN CONTINUE WITH SLIGHT CHC POPS IN THE GRIDS FOR THURSDAY NIGHT AND FRIDAY MORNING FOR NOW. THEREAFTER...DRY WEATHER FORECAST AS WEAK HIGH PRESSURE BUILDS BACK IN. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... HIGH PRESSURE WILL REMAIN OFFSHORE OVERNIGHT AND THROUGH MONDAY. VFR. SOME PATCHY FOG IS POSSIBLE ACROSS OUTLYING TERMINALS OVERNIGHT WITH MVFR VISIBILITIES. WIND WILL BE GENERALLY LIGHT FROM THE SOUTH TO SOUTHWEST TO LIGHT AND VARIABLE INLAND. SE-S SEA BREEZES 8-10 KT DEVELOP AT THE TERMINALS MONDAY AFTERNOON AT ALL BUT KSWF. .OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY... .LATE MON NIGHT...MVFR CONDS POSSIBLE LATE VIA LOW CLOUDS... PATCHY FOG AND SCT SHOWERS. .TUE...CHANCE OF TSTMS WITH MVFR OR LOWER CONDS...ESPECIALLY FROM NYC METRO NORTH/WEST. .TUE NIGHT...MVFR/IFR CONDS LIKELY IN FOG. .WED...CHANCE OF TSTMS WITH BRIEF MVFR OR LOWER CONDS. .THU-FRI...CHANCE OF SHOWERS WITH BRIEF MVFR OR LOWER CONDS. && .MARINE... FORECAST TONIGHT FOR SEAS AND WINDS REMAINS ON TRACK FOR THE AREA WATERS. HI PRES WILL KEEP WINDS AND SEAS BLW SCA LVLS THRU MON NGT. A TROUGH OF LOW PRESSURE APPROACHES ON TUESDAY...THEN A COLD FRONT APPROACHES ON WEDNESDAY AND STALLS JUST SOUTH OF THE WATERS ON THURSDAY. THIS COULD TIGHTEN THE PRESSURE GRADIENT SOMEWHAT TUESDAY AND WEDNESDAY...BUT WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA. IT COULD COME CLOSE TO REACHING CRITERIA THRESHOLDS HOWEVER ON THE OCEAN WATERS TUESDAY AFTERNOON AND EVENING. THEN WITH THE FRONT SETTLING NEARBY THURSDAY...WINDS AND SEAS SHOULD DIMINISH. && .HYDROLOGY... SIGNIFICANT PRECIPITATION COULD OCCUR AT SOME POINT DURING MID WEEK. TUE AND WED BOTH OFFER POTENTIAL FOR AT LEAST LOCALIZED URBAN AND POOR DRAINAGE FLOODING WITH GENERALLY WEAK STEERING FLOW. THE GREATER POTENTIAL APPEARS TO BE WEDNESDAY NIGHT INTO WEDNESDAY EVENING. WILL CONTINUE TO HIGHLIGHT THIS IN THE HWO. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...JMC/JC NEAR TERM...JMC/JM SHORT TERM...JMC LONG TERM...JC AVIATION...GOODMAN MARINE...JMC/JC/JM HYDROLOGY...JMC/JC

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.