Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 250750 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 350 AM EDT MON AUG 25 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN IN CONTROL OF OUR WEATHER THROUGH TUESDAY. A COLD FRONT SHOULD DIG SOUTHEAST INTO THE MID ATLANTIC REGION MID WEEK. IN THE WAKE OF THE COLD FRONT, COOLER AIR SETTLES IN OVER THE REGION FOR THE REMAINDER OF THE WORK WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HIGH PRES OVER THE REGION WILL BRING DRY AND WARM WX TO THE AREA TODAY AS AN UPR LEVEL RIDGE TO THE W BEGINS TO PUSH CLOSER. NELY WIND ERLY WILL BECOME S TO SWLY LATE. CLOUDS WILL BE FEW. MDL GUID WAS IN REASONABLE AGREEMENT ON TEMPS AND WAS GENLY FOLLOWED. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... THE AFOREMENTIONED HIGH WILL REMAIN PARKED OVER THE AREA SO A CLEAR SKY, AND DRY CONDS ARE ANTICIPATED. AGAIN, MOS GUID WAS IN GOOD AGREEMENT AND GENLY FOLLOWED. && .LONG TERM /TUESDAY THROUGH SUNDAY/... CONSIDERABLY DIFFERENT MODEL SOLUTIONS FROM BOTH THE GFS AND ECMWF THAN THE MODEL RUNS 24 HOURS AGO. TUESDAY...START TO SEE SOUTHWESTERLY FLOW DEVELOP IN THE LOW LEVELS AT THE SAME TIME AN UPPER LEVEL SHORT WAVE RIDGE PIVOTS SOUTHEAST OVER THE REGION EARLY IN THE DAY. THE COMBINATION OF BOTH OF THESE WILL RESULT IN RATHER PRONOUNCED WARM UP FOR TUESDAY. HIGHS COULD BE AS MUCH AS 5 DEGREES ABOVE NORMAL. WEDNESDAY AND THURSDAY...THE BIGGEST CHANGE IN THE LATEST LONG RANGE MODEL RUNS IS WITH THE TIMING OF THE COLD FRONT. WHILE THERE HAD BEEN A TREND UP THROUGH YESTERDAY`S 00Z MODEL RUNS OF DELAYING THE ARRIVAL OF THE COLD FRONT (OR NOT EVEN BRINGING IT THIS FAR SOUTH AT ALL), THE 12Z RUNS, AND NOW THE LATEST 00Z RUNS HAVE SPED UP THE ARRIVAL OF THE FRONT. SHOWING THE FRONT ARRIVING IN OUR REGION ON WEDNESDAY OR WEDNESDAY NIGHT. INTERESTINGLY, TO START THIS PERIOD, MID AND UPPER LEVEL FLOW IS NEARLY ZONAL (SUGGESTING THAT THE FRONT MAY NOT DIG AS FAR SOUTH). HOWEVER, BOTH THE GFS AND ECMWF SHOW AN UPPER LEVEL SHORT WAVE TROUGH QUICKLY DIGGING SOUTHEAST OUT OF NORTH CENTRAL CANADA, CROSSING THE NORTHEASTERN U.S. BY WEDNESDAY NIGHT. THERE WILL BE SOME CHANCE OF THUNDERSTORMS ALONG THE FRONT, THOUGH WITH DRIER SOUTHWESTERLY FLOW IN THE PERIODS LEADING UP TO THIS, THERE IS SOME QUESTION OF MOISTURE AVAILABILITY, AND THUS HOW WIDESPREAD PRECIPITATION WILL BE. THE LIMITED LOW LEVEL MOISTURE ALSO HAS AN IMPACT ON INSTABILITY, AS DOES THE EXPECTED NIGHT TIME ARRIVAL OF THE FRONT. THUS...AT THIS TIME SEVERE STORMS SEEM UNLIKELY, BUT IF THE FRONT ARRIVES DURING DAY LIGHT HOURS, NOT COMPLETELY OUT OF THE QUESTION. ON A SIDE NOTE FOR THIS PERIOD, CRISTOBAL IS STILL EXPECTED TO BE WELL OUT TO SEA, AND BY THIS POINT RACING FURTHER AWAY FROM THE REGION. THUS, THE ONLY IMPACTS WE ARE EXPECTING FROM CRISTOBAL ARE LONG PERIOD SWELLS AND AN ENHANCED RIP CURRENT RISK, THOUGH THE TIMING OF BOTH IS UNCERTAIN. FRIDAY...THE CONTINENTAL POLAR AIR MASS SETTLES IN OVER THE REGION, ALBEIT BRIEFLY, BY FRIDAY, LEADING TO A COOL AND DRY DAY. FRIDAY NIGHT THROUGH SUNDAY...AS THE HIGH SHIFTS NORTHEAST OFF THE COAST, LOW LEVEL SOUTHERLY FLOW RETURNS BRINGING A WARMING TREND, AND MORE MOISTURE. THIS COULD SET THE STAGE FOR THE BEST CHANCE OF THUNDERSTORMS OVER THE NEXT WEEK EITHER SATURDAY OR SUNDAY AS A SECOND COLD FRONT COULD APPROACH THE REGION. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. EXCELLENT FLYING WX IS IN STORE THRU THE NR AND SHORT TERM PDS WITH VFR CONDS PREVAILING. HIGH PRES WILL BE THE DOMINANT WX FEATURE. THERE WILL BE HARDLY A CLOUD IN THE SKY AND IT WILL BE DRY. A NELY WIND WILL PREVAIL ERLY UNDER 10 KTS, THEN BY LATE AFTN/ERLY EVE, THE WIND WILL BECOME MORE SLY SWLY AND REMAIN UNDER 10 KTS. THE WIND MAY BECOME VERY LIGHT WLY OVERNIGHT. OUTLOOK... TUESDAY...VFR CONDITIONS EXPECTED. WEDNESDAY THROUGH THURSDAY...MOSTLY VFR CONDITIONS EXPECTED. A SMALL RISK OF THUNDERSTORMS AS A COLD FRONT COULD PUSH THROUGH WEDNESDAY OR THURSDAY. FRIDAY...VFR CONDITIONS LIKELY. && .MARINE... THE SCA WILL REMAIN IN EFFECT AS PREV ISSUED MAINLY FOR SEAS DUE TO THE NELY FLOW. THE FLOW SHOULD EVENTUALLY BECOME MORE SLY THEN SWLY AND THIS SHOULD ALLOW THE SEAS TO SLOWLY SUBSIDE, AFTER WHICH TIME NO ADDITIONAL MARINE HEADLINES WILL BE NECESSARY FOR THE REMAINDER OF THE NEAR AND SHORT TERM PDS. OUTLOOK... TUESDAY...WINDS AND SEAS ARE EXPECTED TO BE BELOW SMALL CRAFT ADVISORY CRITERIA. WEDNESDAY THROUGH FRIDAY...WINDS WILL STAY BELOW SCA CRITERIA. WE COULD BEGIN TO SEE LONG PERIOD SWELLS ASSOCIATED WITH TROPICAL CYCLONE CRISTOBAL, WHICH WILL STAY WELL OUT TO SEA, AS EARLY AS WEDNESDAY. HOWEVER, TIMING AS WELL AS WAVE HEIGHTS ASSOCIATED WITH THESE SWELLS IS STILL VERY UNCERTAIN AT THIS TIME. && .RIP CURRENTS... THE THREAT OF RIP CURRENTS IS HIGH TODAY, AND MAY REMAIN ELEVATED FOR A GOOD PORTION OF THE WEEK. THE COMBINATION OF TODAY`S NEW MOON, LONG FETCH ONSHORE FLOW EARLY AND THEN LONG PERIOD SWELLS ASSOCIATED WITH TROPICAL STORM CRISTOBAL LATER IN THE WEEK SHOULD KEEP AN ELEVATED RISK OF RIP CURRENTS. THE LATEST TRACK OF CRISTOBAL FROM THE NATIONAL HURRICANE CENTER KEEPS CRISTOBAL WELL OFF THE CONUS CST. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR NJZ014-024>026. DE...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR DEZ004. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ452>455. && $$ SYNOPSIS...JOHNSON NEAR TERM...NIERENBERG SHORT TERM...NIERENBERG LONG TERM...JOHNSON AVIATION...JOHNSON/NIERENBERG MARINE...JOHNSON/NIERENBERG RIP CURRENTS...NIERENBERG/JOHNSON

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