Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 261754 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 154 PM EDT SAT JUL 26 2014 .SYNOPSIS... HIGH PRESSURE WILL MOVE FURTHER OUT TO SEA TODAY AS A WARM FRONT APPROACHES FROM THE SOUTHWEST. THIS FRONT WILL LIFT THROUGH THE AREA SUNDAY WITH A COLD FRONT APPROACHING SUNDAY NIGHT. A WAVE OF LOW PRESSURE EXPECTED TO DEVELOP ON THE COLD FRONT...LIFTING THROUGH NEW ENGLAND ON MONDAY AS THE FRONT SLOWLY SLIDES ACROSS. HIGH PRESSURE THEN BUILDS IN BEHIND THE FRONT BY THE MIDDLE OF NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SHORTWAVE ENERGY WILL CONTINUE TO TRACK EASTWARD ACROSS LI/CT THROUGH EARLY AFTERNOON...WITH MID-DECK AND SCATTERED SPRINKLES. AN ISOLATED LIGHT SHOWER IS POSSIBLE ACROSS EASTERN LI/SE CT.. PARTIAL CLEARING EXPECTED ACROSS NYC METRO AND POINTS WEST BY LATE THIS AFTERNOON IN WAKE OF SHORTWAVE AS SEEN ON BY SATELLITE. OTHERWISE...HIGH PRES OFF THE MID ATLANTIC COAST WILL CONTINUE EWD TODAY WITH A MEAN TROUGH PERSISTING ALOFT. ENVIRONMENT DOESN`T LOOK GREAT FOR AFTERNOON CONVECTION...PARTICULARLY IN WAKE OF SHORTWAVE...BUT CAN`T RULE OUT ISOLATED DEVELOPMENT OFF THE HIGHER TERRAIN OF EASTERN PA WORKING INTO AREAS WEST OF THE HUDSON REGION LATE IN THE DAY/EARLY EVE. APPEARS CONVECTIVE ACTIVITY ACROSS SOUTHERN NJ SHOULD REMAIN SOUTH OF THE REGION...WHERE HIGHER THETA-E AIR RESIDES. HIGH AROUND NORMAL LEVELS IN THE LOWER TO MID 80S. THERE IS LOW RISK OF RIP CURRENTS ALONG ATLANTIC FACING BEACHES INTO EARLY THIS AFTERNOON...BECOMING MODERATE LATE TODAY INTO THIS EVENING WITH INCREASING SOUTHERLY WINDS FROM SEA BREEZE DEVELOPMENT. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/... A WARM FRONT APPROACHES TONIGHT AND LIFTS THROUGH SUN MORNING. THE COMBINATION OF A MID LEVEL SHORTWAVE AND THE LEFT EXIT REGION OF A 90KT H250 JET WILL RESULT IN INCREASING CHC`S OF SHRA/TSTMS ACROSS THE AREA LATE TONIGHT INTO SUN MORNING. UNCERTAINTY IN POPS AND SKY BEHIND THE WARM FROPA. IF THERE ARE ANY BREAKS IN THE CLOUDS WE`LL WARM UP FAST AND COULD HIT 90 IN METRO NY/NJ. ANY SUN WILL ALSO RESULT IN DESTABILIZATION DURING THE AFTN AND COULD TRIGGER ADDITIONAL STORMS...SOME OF WHICH COULD REACH SVR LIMITS. MUGGY CONDS WILL BECOME NOTICEABLE AND PERSIST UNTIL THE COLD FRONT PUSHES THROUGH SOMETIME MON NIGHT. THIS IS WHERE THE FORECAST GETS INTERESTING WITH THE FOCUS TURNING TO A WEAKENING CUTOFF LOW DROPPING THROUGH THE UPPER MIDWEST TONIGHT...THE GREAT LAKES SUN AND PIVOTING THROUGH NEW ENGLAND ON MON. SOME OF THE MODEL GUIDANCE IS INDICATING A SECONDARY AREA OF LOW PRES DEVELOPING OVER CENTRAL NJ SUN NIGHT...WHILE OTHERS KEEP THE PARENT LOW IN CONTROL FURTHER N AND W. CONSIDERABLE SPREAD REMAINS AMONGST THE GUIDANCE WITH REGARDS TO TIMING AND TRACK OF THE LOW. THE 00Z NAM IS THE WORST CASE SCENARIO WITH THE LOW TRACKING NE FROM CENTRAL NJ TO MA WITH 60+KT OF 0-6KM BULK SHEAR (~15KT 0-1KM SHEAR)...APPROX 1K J/KG OF SBCAPE...400-500 M2/S2 OF SFC-1KM HELICITY AND AN LCL BELOW 1K FT AROUND 06Z MON. THIS WOULD BE SUFFICIENT FOR ROTATING STORMS. HOWEVER IF THIS SECONDARY LOW DOES NOT DEVELOP THE MOST SEVERE STORMS SHOULD REMAIN FURTHER N AND W. NEEDLESS TO SAY...STILL SOME FAIRLY BIG UNCERTAINTY IN HOW MUCH OF AN IMPACT THIS WILL BE...BUT SINCE THERE IS THE THREAT FOR SVR WX HAVE ADDED ENHANCED WORDING TO THE FORECAST SUN AFTN AND NIGHT. PWATS INCREASING TO NEAR 2 INCHES ALSO INDICATE THE POTENTIAL FOR HEAVY RAIN IN ANY THUNDERSTORMS. FRONT IS SLOW TO MOVE ACROSS THE AREA ON MON...AND THE POTENTIAL FOR MORE SHRA/TSTMS WILL CONTINUE MON AFTN. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... UPPER TROUGH/CUTOFF LOW PERSISTS INTO THE MIDDLE OF THE WEEK WITH WEAK HIGH PRES IN CONTROL AT THE SFC. SCHC/CHC SHRA/TSTMS MON NIGHT/TUE AS A RESULT. WEATHER PATTERN BEGINS TO STABILIZE WITH HEIGHTS BUILDING AS THE UPPER LEVEL TROUGH BEGINS TO LIFT NORTH OF THE REGION DURING THE SECOND HALF OF THE WEEK. AT THE SURFACE...HIGH PRESSURE WILL BEGIN TO BUILD IN FROM THE WEST. THE HIGH PRESSURE CONTINUES TO BUILD IN AND THE UPPER LEVEL TROUGH AMPLITUDE CONTINUES TO WEAKEN WITH TIME THROUGH THE REST OF THIS PERIOD. THIS WILL ALLOW FOR A DRY AIRMASS TO ENCOMPASS THE REGION. TEMPERATURES WILL NOT DEVIATE TOO MUCH FROM NORMAL. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... WEAK HIGH PRESSURE AND SURFACE TROUGH NEARBY REMAIN INTO THIS EVENING. A WARM FRONT APPROACHES TONIGHT AND PASSES THROUGH SUNDAY MORNING. VFR THROUGH THIS EVENING. SW TO S WINDS 10-15KT THIS AFTN...DIM 5-10KT TONIGHT. A FEW GUSTS UP TO 20KT ARE POSSIBLE INTO EARLY EVENING...HOWEVER NOT FREQUENT ENOUGH TO INCLUDE IN THE TAFS. SHOWERS SUNDAY MORNING WITH A CHANCE OF TSTMS. ADDITIONAL SHRA/TSTMS POSSIBLE SUN AFTN. .OUTLOOK FOR 18Z SUN THROUGH THU... .SUN AFTN...MAINLY VFR. ISO/SCT SHRA/TSTMS. .SUN NIGHT...SHRA AND SCT TSTMS. CHC TEMPO SUB-VFR. .MON...MAINLY VFR. CHC SHRA/TSTMS. CHC TEMPO SUB-VFR. .TUE-THU...VFR. && .MARINE... SUB SCA CONDS TODAY...WITH SOUTH WINDS INCREASING SUNDAY AND SUNDAY NIGHT OUT AHEAD OF LOW PRESSURE AND ASSOCIATED COLD FRONT. SEAS BUILD AS A RESULT LATE SUNDAY INTO SUNDAY NIGHT AND REMAIN RATHER ROUGH MONDAY. SMALL CRAFT ADVISORY HEADLINES MAY BE NEEDED EVENTUALLY FOR THE SUNDAY NIGHT THROUGH MONDAY TIME FRAME ACROSS THE OCEAN WATERS. WINDS GRADUALLY SHIFT TO THE WEST BEHIND THE SLOW MOVING FRONT LATE MONDAY AND MONDAY NIGHT...AND SPEEDS DIMINISH SOMEWHAT. WEST OR NORTHWEST WINDS CAN BE EXPECTED TUESDAY AND WEDNESDAY. ROUGH SEAS SUBSIDE TUESDAY AND WEDNESDAY. && .HYDROLOGY... UNSETTLED WEATHER WITH SCATTERED TO NUMEROUS SHOWERS/TSTMS ARE FORECAST LATE TONIGHT THROUGH MONDAY. ANY OF THESE STORMS HAVE THE POTENTIAL TO PRODUCE HEAVY DOWNPOURS. SIGNIFICANT UNCERTAINTY STILL EXISTS WITH TIMING AND AMOUNTS THOUGH. IT LOOKS LIKE THE HIGHER POTENTIAL FOR HEAVY RAIN IS SUNDAY AFTN AND SUNDAY NIGHT WITH HIGHER PWATS OF 1.5 TO 2 INCHES ACROSS THE REGION. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION...PW MARINE... HYDROLOGY...

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