028 FXUS61 KPHI 250939 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 539 AM EDT SAT MAY 25 2013 .SYNOPSIS... STRONG LOW PRESSURE EAST OF CAPE COD WILL DRIFT NORTHWARD INTO THE MAINE ON SUNDAY. IT THEN WILL SLOWLY WEAKEN MONDAY OVER THE MARITIMES AS HIGH PRESSURE MOVES INTO THE MID ATLANTIC STATES. A WARM FRONT DEVELOPS OVER THE DELMARVA TUESDAY AND SLOWLY LIFTS NORTHEAST OF OUR AREA BY LATE WEDNESDAY. THEREAFTER... SUMMERLIKE BERMUDA HIGH PRESSURE SHOULD BE OUR PRIMARY WEATHER INFLUENCE THURSDAY INTO NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LOW PRESSURE CONTINUES TO CIRCULATE OVER THE NEW ENGLAND WATERS...WHILE SLOWLY DEEPENING. HIGH PRESSURE IS TO THE WEST OVER THE UPPER GREAT LAKES AND OHIO VALLEY. THE NW FLOW BETWEEN THESE SYSTEMS WILL CAUSE WINDS TO BE GUSTY FROM THE NW TODAY. WIND GUSTS OF 25 TO 30 MPH WILL OCCUR AT TIMES. CLOUDS AND A FEW SHOWERS WILL LINGER NORTH/EAST THIS MORNING BEFORE DIMINISHING. PARTLY CLOUDY SKIES SOUTH/WEST WILL BECOME MOSTLY CLR DURING THE MORNING. HIGH TEMPERATURES WILL REMAIN WELL BELOW NORMAL FOR LATE MAY WITH HIGHS MID 50S TO LOW 60S NORTH AND LOW TO MID 60S ELSEWHERE. THIS WOULD BE 10 TO 15 DEGREES BELOW NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SUNDAY/... THE LOW ACROSS NEW ENGLAND WILL CONTINUE TO BRING COOLER AND DRIER AIR ACROSS THE REGION. HIGH PRESSURE WILL INCH EASTWARD FROM THE OHIO VALLEY. SKIES WILL BE MAINLY CLR ACROSS THE AREA TONIGHT. A FEW LINGERING CLOUDS FAR NORTH/EAST SHOULD DISSIPATE THIS EVENING. IT WILL REMAIN BREEZY WITH NORTHWEST WINDS 10 TO 15 MPH WITH SOME G20 MPH EARLY. LOW TEMPERATURES (BASED MOSTLY ON MAV MOS) WILL DIP INTO THE UPPER 30S TO LOW 40S NORTH AND MID 40S TO LOW 50S SOUTH. PROBABLY NO THREAT OF ANY FROST FAR NORTH...DUE TO THE CONTINUATION OF LIGHT-MOD WINDS OVERNIGHT. && .LONG TERM /SUNDAY THROUGH FRIDAY/... 500MB: AN UNUSUALLY COLD STRONG CLOSED LOW WILL BE LIFTING NWD FROM MAINE ON SUNDAY WITH A LARGE STRONG VERY WARM RIDGE BUILDING EASTWARD FROM THE MIDWEST ON MONDAY AND TUESDAY THEN BECOMES LOCKED IN ALONG THE MID ATLANTIC COAST FOR THE END OF THE WEEK AND POSSIBLY BEYOND. TEMPERATURES: CALENDAR DAY AVG TEMPS NEARLY 10 DEGREES BELOW NORMAL ON SUNDAY WILL WARM TO NEAR 5 DEGREES BELOW NORMAL MONDAY AND TUESDAY... AND THEN FROM WEDNESDAY ONWARD...A WARMER THAN NORMAL PERIOD OCCURS AS THE SUMMER RIDGE REPLACES THIS CURRENTLY OUT OF SEASON COLD DAMP BLUSTERY WEATHER. TEMPERATURES COULD AVERAGE ALMOST 10 DEGREES ABOVE NORMAL THURSDAY AND FRIDAY. FROST: SMALL CHANCE FOR A TOUCH OF FROST IN MONROE COUNTY EARLY MONDAY MORNING. HWO. HEAT: GREATER POTENTIAL FOR A HEAT WAVE BEGINNING WED OR THU INTO THE START OF THE WEEKEND. NOT YET IN HWO. NEED A LITTLE MORE CONTINUITY FOR THIS DAY 5-7 OR DAY 6-8 POTENTIAL HOT SPELL. THE DAILIES BELOW... SUNDAY AND MONDAY ARE BASED ON 50 50 BLENDED GFS/NAM MOS GUIDANCE AND THEN TUESDAY IS 00Z/25 GFS MEXMOS. TUE NIGHT ONWARD THROUGH FRIDAY IS BASED PRIMARILY ON THE 0543Z/25 NCEP EXTENDED GUIDANCE WHICH WAS MODIFIED UPWARD ON THE DAYTIME TEMPS WHERE THE GFS MEXMOS OR 00Z/25 ECMWF 2M TEMPS WERE WARMER THAN HPC. ALL THIS DATA IS CHECKED AGAINST ENSEMBLE POP GUIDANCE AS WELL AS THE ECMWF MASS FIELDS AND THEIR 2M TEMPS. SUNDAY...PARTLY SUNNY DAY AND BLUSTERY. NW GUSTS 25-30 MPH. CLEAR AND CHILLY AT NIGHT. LOW PROB ISOLATED FROST POCONOS. DESPITE CLIMO IMPACT ON THE GUIDANCE...WHICH MIGHT FORECASTING THE NIGHTTIME TEMPS A TAD ON THE MILD SIDE MONDAY MORNING...IT JUST APPEARS THE NIGHT IS TOO SHORT AFTER A DAYTIME MAX IN THE 60S TO PERMIT FROST. MONDAY...MOSTLY SUNNY. W-NW G TO 15 MPH. 35 TO 40 DEGREE DIURNALS IN THE COUNTRYSIDE. TUESDAY INTO WEDNESDAY...A SMALL WARM FRONTAL SHOWER RISK BUT OVERALL I THINK ACCEPTABLE FOR OUTDOOR ACTIVITY. VARIABLE CLOUDS. S-SW G 15 TUESDAY AND WSW ON WED. TEMPS THU AND FRI COULD RUN 3 DEGREES WARMER THAN WHAT WE ARE CURRENTLY FCSTG IN THE 330 AM KPHI FCST PACKAGE. IT IS DAY 6-7 BUT IT LOOKS HOT IN THE 90-93F RANGE. FOR NOW A MORE CONSERVATIVE AROUND 90F FCST. THURSDAY...SUNNY AND PROBABLY HOT. SW G 15. 16-17C AT 850MB FRIDAY...PARTLY SUNNY AND PROBABLY HOT. FOR NOW THE 12Z/24 ECMWF IDEA OF A BACKDOOR COOL FRONT WAS SQUASHED BY ITS 00Z/25 DETERMINISTIC RUN AND THE GEFS ARGUES STRONGLY AGAINST A BACKDOOR. SW G 15 MPH. 16-17C AT 850MB. && .AVIATION /10Z SATURDAY THROUGH WEDNESDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. LOW PRESSURE AT THE SFC AND ALOFT WILL CONTINUE TO SPIN ABOUT ACROSS NEW ENGLAND TODAY AND THEN SLOWLY MOVE AWAY TONIGHT. THIS SYSTEM WILL CONTINUE TO PRODUCE ABUNDANT CLOUDINESS NORTH/EAST WITH IMPROVING CONDITIONS ARRIVING FROM THE SOUTH/WEST THROUGH THE DAY. EVEN WITH THE CLOUDS (AND EARLY MORNING SHOWERS)...CONDITIONS ARE EXPECTED TO REMAINS VFR AT THE TERMINALS. WINDS WILL BE GUSTY TODAY AND INTO EARLY TONIGHT WITH NORTHWEST WINDS 10 TO 20 G25 EARLY...THEN 15 TO 25 G30 KT FROM LATE MORNING INTO THE EARLY EVENING. WINDS GRADUALLY SUBSIDE OVERNIGHT SAT NIGHT. SKIES SAT NIGHT INTO SUN WILL BE MOSTLY CLR. OUTLOOK... SUNDAY...MAINLY VFR CONDITIONS WITH SCT-BKN CLOUDS AOA 5000 FT. GUSTY NORTHWEST WINDS TO NEAR 25 KT DURING THE DAY DIMINISH AT NIGHT AS SKIES CLEAR. MONDAY...VFR GENERALLY CLEAR WITH WEST NORTHWEST WINDS G NEAR 15 KT. TUESDAY THROUGH WEDNESDAY...MOSTLY VFR CONDITIONS. SMALL CHANCE SUB- VFR CIGS/VSBYS IN SHWRS TUESDAY NIGHT WITH A WARM FRONT LIFTING THROUGH THE REGION. && .MARINE... WE WILL PUT UP THE GALE AT THE NORTHERN TWO COASTAL ZONES WITH THE 400 AM CWF ISSUANCE. THE GALE FLAG WILL CONTINUE THOUGH THE TODAY/TONIGHT PERIOD WITH THE DECENT PRESSURE GRADIENT ACROSS THE REGION AND THE COLD NORTHWEST FLOW. THE ONLY WEATHER OF SIGNIFICANCE IN THE SHORT TERM WILL BE SOME MORNING CLOUDS/SHOWERS ACROSS THE NJ COASTAL WATERS WHICH WILL GRADUALLY ERODE FROM S TO N TODAY. WINDS WILL DECREASE A LITTLE TONIGHT...WITH GALES PROBABLY BEING CONVERTED BACK TO SCA FLAG OVERNIGHT. OUTLOOK... LEFTOVER SCA WINDS AND SEAS SUNDAY (AFTER THE GALE SUBSIDES) THEN NO HEADLINES ANTICIPATED SUNDAY NIGHT THROUGH AT LEAST EARLY WEDNESDAY. THERE MAY BE AN SCA LATE WED BUT ITS A SMALL CHANCE ATTM AND CAPPED SEAS AT 5 FT DUE TO WAA. THAT 5 FEET LATE WED FCST MAY ALSO BE TOO HIGH BY A FOOT OR SO. && .TIDES/COASTAL FLOODING... THE LOW WATER ADVISORY ACROSS DEL BAY WILL CONTINUE THROUGH 800 AM. THE DEPARTURES OVERNIGHT HAVE GONE DOWN TO -1.5 TO -2.5 BELOW NORMAL AND THEY HAVEN'T CHANGED MUCH AS THE LOW TIDE HAS ARRIVED ACROSS THE BAY. IF IT APPEARS THAT THESE DEPARTURES WILL CARRY UP INTO THE DEL RIVER...AN SPS WILL BE ISSUED SHORTLY. && .RIP CURRENTS... THERE IS A MODERATE RISK OF RIP CURRENTS FORECAST FOR TODAY AND PROBABLY TOMORROW. THEREAFTER...FOR MEMORIAL DAY AND TUESDAY THE OUTLOOK IS FOR A LOW RISK FOR THE FORMATION OF RIP CURRENTS AS WINDS AND SWELLS DIMINISH. SSTS ALONG THE COAST ARE QUITE VARIABLE...ESPECIALLY NJ WHERE ITS STILL CHILLY WATERS NEAR ATLANTIC CITY. && .CLIMATE... THE MONTHLY AVERAGE AT PHL SHOULD COME IN ABOUT 1 DEGREE ABOVE NORMAL BASED ON THE LATEST PROJECTIONS. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...GALE WARNING UNTIL 2 AM EDT SUNDAY FOR ANZ430-431-450>455. LOW WATER ADVISORY UNTIL 8 AM EDT THIS MORNING FOR ANZ430-431. && $$ SYNOPSIS...DRAG NEAR TERM...O'HARA SHORT TERM...O'HARA LONG TERM...DRAG AVIATION...DRAG/O'HARA MARINE...DRAG/O'HARA TIDES/COASTAL FLOODING... RIP CURRENTS... CLIMATE... 538