AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 748 PM EDT FRI JUL 8 2011 .SYNOPSIS... LOW PRESSURE IN DELAWARE WILL MOVE OUT TO SEA OVERNIGHT ENDING THIS WIDESPREAD EPISODE OF HEAVY SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL BUILD INTO OUR AREA DURING SATURDAY AND BE OVER THE REGION SUNDAY AND INTO MONDAY. ANOTHER FRONT MAY BRING MORE UNSETTLED CONDITIONS TO THE REGION LATER MONDAY INTO TUESDAY. && .NEAR TERM /THROUGH SATURDAY/... SPC SVR WATCH 610...ANOTHER PORTION TO BE CANCELLED AROUND 755PM....AND REDUCED THUNDER CHANGES. SO WHILE REMAINDER WATCH CONTS... NO BIG RENEWAL OF HEAVY CONVECTION EXPECTED IN E PA AND NW NJ. JUST DEALING WITH LEFTOVERS THERE NOW. WILL STEP IT DOWN 1 HR AT A TIME. WCN/HWO/ZFP UPDATED AROUND 625P. FFA CANCEL ARD 8PM EXCEPT SE PORTION WHERE ON GOING HEAVY RAINS. ANY RUNOFF FLOODING MAY TAKE SEVERAL HOURS TO SUBSIDE AFTER THE RAIN QUITS THIS EVENING. ANY DAMAGE REPORTS YOU HAVE...BE IT FROM FLOODING/WIND...PLEASE RELAY AS SOON AS POSSIBLE TO THE NWS. PATCHY FOG WILL DEVELOP LATE TONIGHT ONCE THE RAINS END AND SKY COVER BEGINS TO BREAK UP A BIT. FOG WAS NOT INCLUDED IN THE GRIDS ATTM...SINCE THERE IS ALREADY PLENTY OF WORDINESS WITH THE SVR/FLOOD WORDING ALREADY IN THERE. && .SHORT TERM /SATURDAY NIGHT/... THE LAST OF THE CLOUDS AND SCATTERED SHOWERS ASSOCIATED WITH THE FRONT AND LOW PRESSURE AREAS FROM THE NEAR TERM WILL BE PASSING OFF THE COAST SAT MORNING. LOW CHC POPS AND A FEW CLOUDS ARE STILL IN THE GRIDS FOR THE MORNING AREAS ACROSS ERN DELAWARE AND THE SRN COASTAL WATERS. HIGH PRESSURE WILL BUILD IN SAT AND REMAIN INTO MONDAY. A DRY FORECAST IS EXPECTED WITH MAINLY CLR SKIES. TEMPERATURES WILL STILL BE VERY WARM...BUT THE LOWER HUMIDITY VALUES WILL MAKE THINGS COMFORTABLE. SAT NIGHT WILL BE COOL WITH LOWS IN 50S ACROSS THE NORTHERN AREAS AND LOW TO MID 60S IN MOST OTHER AREAS. && .LONG TERM /SUNDAY THROUGH FRIDAY/... THE MODELS HAVE BEEN PRETTY CONSISTENT THAT THE FLAT HEAT RIDGE OVER THE EASTERN CONUS WILL RETROGRADE SLIGHTLY TO THE SOUTHWEST. AFTER THE 500MB TROF PASSES, A CANADIAN HIGH PRESSURE SYSTEM WILL BUILD INTO THE NORTHEASTERN CONUS. THERE REMAINS DIFFERENCES AS TO HOW ROBUST THE CONVECTION WILL BE WITH THE COLD FRONTAL PASSAGE MONDAY NIGHT INTO TUESDAY. TODAY THE TIMING LOOKS SLIGHTLY BETTER FOR A MORE ACTIVE TUESDAY. WE OPTED FOR POPS CLOSER TO THE GFS VS WHAT WOULD BE INFERRED USING THE ECMWF. AFTER THE FRONT CLEARS THE REGION, OUR CWA SHOULD HAVE A COUPLE OF DAYS WITH QUITE PLEASANT DEW POINTS. THERE ARE DIFFERENCES AS TO HOW COOL IT WILL GET, ALTHOUGH THE GAPS ARE SMALLER THAN YESTERDAY. BASED ON HOW ABOVE NORMAL THIS METEOROLOGICAL SUMMER HAS BEEN SO FAR, WE HAVE OPTED TO KEEP MAX TEMPS TOWARD THE WARMER END OF THE ENSEMBLE MEMBERS THROUGHOUT THE LONG TERM. REGARDLESS AFTER A HOT AND HUMID TUESDAY, LOWER TEMPERATURES ARE IN STORE, ESPECIALLY AT NIGHT, FOR THE REST OF THE LONG TERM PERIOD. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. TONIGHT...PATCHY MVFR OR IFR CONDS IN ST/FOG SPREAD S BEHIND THE DEPARTING LOW WITH HEAVY CONVECTION MOVING OUT TO SEA BY 04Z. SATURDAY AFTER 12Z...ANY IFR STRATUS ALONG AND SOUTH OF A KILG- KACY LINE THROUGH ABOUT 1400 UTC. AFTER THE SURFACE LOW PULLS AWAY...THE LOW LEVEL INVERSION SHOULD BREAK...AND VFR CONDITIONS ARE EXPECTED EVERYWHERE FOR THE REMAINDER OF THE DAY. CONVECTIVE TEMPERATURES COULD BE MET IN THE AFTERNOON...WHICH SHOULD RESULT IN SCATTERED CUMULUS. HOWEVER...INCREASING STABILITY SHOULD LIMITED ANY CONVECTIVE POTENTIAL. OUTLOOK... SAT NIGHT AND SUNDAY...WEAK HIGH PRESSURE BUILDING INTO THE REGION SHOULD RESULT IN VFR CONDITIONS. SUN NIGHT...VFR TO START BUT WAA MVFR CIGS MAY DEVELOP IN E PA LATE. MONDAY...WARM AIR ADVECTION AHEAD OF A FRONTAL BOUNDARY COULD RESULT IN SCATTERED THUNDERSTORMS LATE MONDAY OR MONDAY NIGHT...BUT OVERALL VFR CONDITIONS ARE EXPECTED. MVFR FOG IS POSSIBLE EARLY TUESDAY. TUESDAY...MVFR FOG POSSIBLE EARLY OTHERWISE VFR WITH A CHANCE OF TSTMS AND ASSOCIATED LOWER CONDITIONS. && .MARINE... NO MARINE HEADLINES EXCEPT THE SEVERE THUNDERSTORM WATCH 610 THROUGH 01Z. CONVECTIVE BOW SWEEPING DEL BAY AT THIS TIME WITH STRONG WLY GUSTS. SEAS OF 5 FT TONIGHT AT 44009 MAY GRAZE OUR DEL WATERS BUT FOR NOW CONSERVATIVE APPROACHING DUE TO WAVE GENERATION THERE ON SSW WIND. ASIDE FROM CONVECTIVE GUSTS TONIGHT...THERE MAY BE SOME FOG LATER ON WHICH IS NOT YET ACCOUNTED FOR IN THE GRIDS. THIS WEEKEND LIGHT WIND WITH AFTERNOON SEA BREEZES POSSIBLE. THE RETURN FLOW AROUND THE HIGH COULD RESULT IN WINDS AND SEAS INCREASING MONDAY INTO TUESDAY. THERE IS A CHANCE FOR WINDS TO GUST TO 25 KNOTS DURING THIS TIME...BUT CONFIDENCE IN THIS IS LOW FOR NOW. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...FLASH FLOOD WATCH UNTIL 4 AM EDT SATURDAY FOR PAZ054-055- 060>062-067>071. NJ...FLASH FLOOD WATCH UNTIL 4 AM EDT SATURDAY FOR NJZ001-007>010- 012>027. DE...FLASH FLOOD WATCH UNTIL 4 AM EDT SATURDAY FOR DEZ001>004. MD...FLASH FLOOD WATCH UNTIL 4 AM EDT SATURDAY FOR MDZ008-012-015- 019-020. MARINE...NONE. && $$ SYNOPSIS...DRAG 747P