Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 300721 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 321 AM EDT SUN AUG 30 2015 .SYNOPSIS... HIGH PRESSURE WILL SLIDE OVER THE EASTERN U.S. THROUGH THE WORK WEEK LEADING TO A MOSTLY HOT AND DRY PATTERN. A WEAK COLD FRONT MAY SLIDE INTO OUR REGION ON THURSDAY. A LOW OFF SHORE AND A HIGH TO OUR NORTHEAST MAY PROVIDE SOME COOLER CONDITIONS FOR NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HI PRES WILL REMAIN OVER THE REGION TODAY AND SLOWLY MOVE EWD. AS IT DOES, BOTH CLOUD COVER AND MOISTURE WILL INCREASE. A S/WV WILL APPROACH FROM THE W DURG THE AFTN HOURS AND THIS FEATURE COULD TRIGGER A SHWR OR TSTM, MAINLY FOR NRN AND WRN AREAS, SO WILL CONTINUE VERY LOW POPS IN THESE LOCATIONS. HOWEVER, THE OVERALL AMS IS VERY DRY, SO IT WOULDN`T BE SURPRISING IF NOTHING HAPPENED EITHER. TEMPS WILL BE A BIT WARMER THAN SATURDAY AND DE PTS WILL CREEP UP AS WELL. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/... ANY ISOLD SHWRS OR TSTMS WILL COME TO AN END AND THEN EXPECT JUST A PCLDY SKY WITH GRADUALLY INCREASING DEW PTS, AS THE HIGH REMAINS THE DOMINANT WX FEATURE AS WE CLOSE OUT AUGUST AND METEOROLOGICAL SUMMER. && .LONG TERM /MONDAY THROUGH SATURDAY/... SOME SHIFTS IN TRACKS AND TIMING WITH THE LATEST MODEL RUNS, BUT THE MAIN STORY REMAINS THE HIGH SLIDING OVER THE REGION FOR MUCH OF THE WORK WEEK. MONDAY THROUGH WEDNESDAY...MAY SEE A FEW LINGERING SHOWERS OR THUNDERSTORMS MONDAY MORNING AS AN UPPER LEVEL SHORT WAVE TROUGH MOVES FURTHER AWAY FROM THE REGION, BUT OTHERWISE PRECIPITATION CHANCES THROUGH THIS PERIOD ARE VERY SLIM. SHOULD SEE A MODEST WARMING TREND FROM MONDAY INTO TUESDAY AS THE RIDGE AXIS SLIDES OVERHEAD, THUS LEADING TO INCREASING 1000-500 MB THICKNESSES FOR THE REGION. EVEN WITH THIS HIGH AMPLITUDE RIDGE THOUGH, HIGHS SHOULD STAY WELL BELOW RECORDS, AND HEAT INDEX VALUES SHOULD STAY IN THE LOWER TO MID 90S. THURSDAY...A BIT MORE UNCERTAINTY IN THIS PERIOD, SPECIFICALLY WITH THE EVOLUTION OF THE WEAK COLD FRONT. SOME MODELS ARE NOW STALLING THIS FRONT WELL NORTH OF THE REGION, OR SHOWING THE TEMPERATURE GRADIENT ALMOST DISAPPEAR COMPLETELY BY THE TIME IT REACHES OUR REGION. FOR NOW THOUGH, HAVE STAYED CLOSE TO THE PREVIOUS FORECAST FOR BOTH TEMPERATURES AND PRECIPITATION CHANCES, AS THE UPPER LEVEL SHORT WAVE TROUGH COULD PROVIDE ENOUGH LIFT AND FOCUS FOR CONVECTION EVEN WITHOUT THE FRONT, AND STILL THINK THERE IS A CHANCE THE FRONT WILL REACH THE AREA GIVEN THAT THE MODELS TEND TO UNDERESTIMATE HOW FAR SOUTH FRONTS WILL PROPAGATE IN THE TRANSITION SEASONS. FRIDAY THROUGH SATURDAY...STAYED RELATIVELY CLOSE TO THE PREVIOUS FORECAST AS THERE ARE SOME LARGE DIFFERENCES AMONG THE LONG RANGE MODELS IN THIS PERIOD. THE GFS SHOWS STEADY ON SHORE FLOW AS A SURFACE HIGH DEVELOPS TO OUR NORTHWEST. MEANWHILE, THE ECMWF SHOWS A VERTICALLY STACKED, AND NEARLY STATIONARY, LOW TO OUR SOUTHEAST. EITHER SOLUTION THOUGH DOES LOOK TO BRING A COOLING TREND THROUGH THE WEEKEND. && .AVIATION /07Z SUNDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. VFR CONDS WILL BE THE RULE THRU THE TAF PD, WITH HI PRES IN CONTROL. A WEAK DISTURBANCE WILL MOVE THRU DURG THE LATE AFTN HOURS AND COULD TOUCH OFF A STRAY SHRA OR TSRA MAINLY FOR KRDG OR KABE. HOWEVER, OVERALL CHCS ARE VERY LOW AND, THEREFORE, WILL NOT BE MENTIONED IN THE TAFS. OTHERWISE, EXPECT A SW WIND TO DEVELOP Y LATE MRNG GENLY 10 KTS OR LESS. WIND WILL THEN DECREASE AFTER SUNSET. OUTLOOK... MONDAY THROUGH WEDNESDAY...VFR CONDITIONS EXPECTED THOUGH LOCALIZED MVFR CONDITIONS WITH FOG POSSIBLE EACH MORNING. THURSDAY...MOSTLY VFR CONDITIONS. ISOLATED THUNDERSTORMS POSSIBLE. && .MARINE... NO MARINE FLAGS ARE ANTICIPATED THRU THE NR AND SHORT TERM PDS. SEAS WILL GENLY BE IN THE 2 TO 4 FT RANGE. WIND WILL GENLY BE SW IN THE 10 TO 15 KT RANGE WITH GUSTS AS HIGH AS 20 KT. OUTLOOK... MONDAY THROUGH THURSDAY...WINDS AND SEAS SHOULD STAY WELL BELOW SMALL CRAFT ADVISORY CRITERIA. WATER TEMPERATURES ARE ABOVE NORMAL. && .RIP CURRENTS... A MODERATE RISK WILL BE MAINTAINED IN NJ ONCE AGAIN TODAY, AS WE WILL HAVE 24-4 FT SEAS, SW WIND THAT COULD GUST AS HIGH AS 20 KT AND SE SWELL. WE WILL STILL BE INFLUENCED BY THE NEARLY FULL MOON AS WELL AND HAVE LONG PERIODS...AROUND 10 SECONDS. IN DELAWARE, THE RISK REMAINS LOW. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...JOHNSON NEAR TERM...NIERENBERG SHORT TERM...NIERENBERG LONG TERM...JOHNSON AVIATION...JOHNSON/NIERENBERG MARINE...JOHNSON/NIERENBERG RIP CURRENTS...

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