Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 010800 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 400 AM EDT WED OCT 1 2014 .SYNOPSIS...
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LOW PRESSURE WILL REDEVELOP OFF THE NEW ENGLAND COAST THROUGH THURSDAY AS HIGH PRESSURE OVER EASTERN CANADA BUILDS IN FROM THE NORTHEAST. A STRONG LOW PRESSURE SYSTEM OVER THE CENTRAL UNITED STATES WILL MOVE NORTHEASTWARD INTO ONTARIO BY FRIDAY AND ITS ASSOCIATED STRONG COLD FRONT WILL MOVE THROUGH THE REGION FRIDAY NIGHT INTO SATURDAY. HIGH PRESSURE WILL BUILD IN BEHIND THE DEPARTING FRONT. ANOTHER COLD FRONT WILL CROSS THE REGION AROUND MONDAY.
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&& .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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TROUGH AXIS SHOWERS AND TSTMS IN EASTERN PA TO CHESAPEAKE BAY HAVE DIMINISHED CONSIDERABLY SINCE 5Z AND AS OF THIS 0715Z (315 AM)...JUST A FEW SHOWERS VCNTY AND WEST OF KRDG. HOWEVER...FROM THE EAST OFF THE ATLC...WE`RE SEEING VIA TPHL INCREASING SHOWER COVERAGE AND SIGNIFICANT HOURLY RAINFALLS THAT ARE IN THE .03/HR RANGE. SO THE POPS TODAY SHOW A DRY SLIT ON THE SOUTHERN DELMARVA AND DECENT POPS NW NJ THRU EASTERN NJ AND ALSO VCNTY KRDG. HAVE DROPPED THE FOG IDEA THIS MORNING...TOO MUCH MULTI LAYER CLOUDS COMBINED WITH A LIGHT NE WIND WILL PROBABLY PREVENT MUCH SETTLING OF THE CIGS. THIS WAS CK`D USING UPS CROSSOVER. DURING THE DAY TODAY...INSTABILITY SCT SHOWERS ANTICIPATED AS OUTLINED ABOVE...MAINLY W FRINGE WITH THE ONSHORE SHOWERS THIS MORNING POSSIBLY DRYING OUT THIS AFTN BUT NOT SURE OF THAT DRYING OUT. PWAT CONTINUES 1.2 INCHES SO SOME AREAS WILL RECEIVE BENEFICIAL RAINFALL...MAINLY EASTERN AND NORTHERN NEW JERSEY AND POSSIBLY VCNTY KRDG. 00Z/1 NSSL WRF FAVORS EASTERN NJ. OVC SKIES THIS MORNING SHOULD BRIGHTEN OR THIN A BIT THIS AFTN TO REVEAL A LITTLE SS. TEMPS/WINDS/DEWS ARE A 50 50 BLEND OF THE 100Z/1 NAM/GFS MOS. POPS ARE A 3 WAY BLEND OF THE 00Z/1 GFS/NAM MOS AND THE 21Z/30 SREF.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/...
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THERE MAY BE EVENING PARTIAL CLEARING BEFORE BL RH SATURATES AND DEVELOPS LOWS CLOUDS AND POSSIBLY PATCHY FOG. GFS MOS TEMPS LOOK FAR TOO COLD SINCE THE LOW PRESSURE SYSTEM IS FAR TO THE EAST AND THE CAA IS WEAK. USED THE NAM MOS TEMPS FOR LOWS WHICH ARE SEVERAL DEGREES WARMER THAN THE GFS MOS. EVEN THESE WERE RAISED A DEG OR TWO. DEWS WERE NAM MOS. WINDS WERE A 50 50 BLEND OF THE GFS/NAM MOS POPS WERE BLENDED GFS/NAM MOS AND LOWERED IN THE SW PTN OF THE FCST AREA USING THE 21Z/30 SREF.
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&& .LONG TERM /THURSDAY THROUGH TUESDAY/...
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AN AREA OF HIGH PRES OVER THE CAN MARITIMES WILL NOSE WWD OVER THE AREA ON THU AND EXPECT A DRY DAY BUT ABUNDANT CLOUDINESS AS ELY FLOW WILL PERSIST. THIS HIGH WILL REMAIN IN PLACE FOR THU NIGHT INTO ERLY FRI WITH LOW PRES WELL OFF THE CST OF NEW ENG. ATTN THEN TURNS TO THE CNTRL CONUS WHERE A POTENT LOW PRES SYS WILL TAKE SHAPE BEGINNING THU NIGHT. THIS LOW WILL MOVE NNEWD AND STRENGTHEN AS IT MOVES INTO OR TOWARD ONTARIO ON FRI. THE MDLS ALL AGREE ON THE FACT THAT THIS LOW DEVELOPS AND MOVES INTO OR TOWARD ONTARIO DURG THIS TIME FRAME, THEY DIFFER A BIT ON THE DETAILS, AS SHOULD BE EXPECTED. THE GFS, NAM/WRF AND CMC HAVE A SINGLE LOW STRUCTURE AND BRING THE LOW INTO ONTARIO BY 03/18Z. ON THE OTHER HAND, THE ECMWF HAS A DOUBLE LOW STRUCTURE AT 03/18Z AND IS SIGNIFICANTLY WEAKER AT THIS TIME FRAME (BY ABOUT 10 MB) THAN ANY OTHER MDL. IT THEN IS INTERESTING THAT BY 78 AND 84 HRS THE ECMWF MDL HAS THE STRONGEST SOLN WITH THE LOW, BUT IT IS FURTHER S AND E WITH THE LOW CENTER THAN THE OTHER MDLS. THE CDFNT ASSOCD WITH THIS LOW WILL BEGIN MOVG EWD AND THERE CUD BE SOME PRECIP IN WRN AREAS BY SUNSET FRI, THOUGH CONFIDENCE IS LOW. PRECIP CHCS WILL INCREASE FROM W TO E FRI NIGHT AND THERE ARE TIMING DIFFS WITH THE MDLS AS WELL. THE GFS AND NAM/WRF GENLY KEEP THE HEAVIEST PRECIP W OF THE I-95 CORRIDOR THRU DAYBREAK SAT WHILE THE ECMWF AND CMC ARE FURTHER E. THE GFS THEN BRINGS THE HEAVIER PRECIP THRU DURG THE MRNG HOURS WHILE THE ECMWF IS ABOUT 6 HOURS FASTER. THEN PRECIP ENDS FROM SW TO NE DURG THE DAY BEHIND THE CFP AS A WSHFT FROM E TO WNW BRINGS IN DRIER AIR. THERE IS SILL ENOUGH UNCERTAINTY IN THE MDLS TO KEEP CONFIDENCE LWR THAN AVERAGE. THE ECMWF IS OFTEN TOO SLOW WITH FRONTAL TIMING, SO ITS INTERESTING THAT IT IS THE FASTER SOLN HERE. ONE NOTICEABLE TREND IN THE 01/00 GUID IS IMPROVEMENT IN THE SECOND HALF OF SAT, SO HAVE LOWERED POPS DURG THIS TIME FOR THIS FCST ISSUANCE. WITH THAT SAID, HIGH PRES MOVES IN BEHIND CFP AND SAT NIGHT THRU MON LOOK DRY. ANOTHER WK CDFNT WILL CROSS THE REGION ON MON, BUT ATTM NOT ENOUGH CONFIDENCE TO PUT IN POOPS AS THE ECMWF IS DRY WHILE THE GFS HAS SOME LOW POPS. ON TUE, THERE CUD BE SOME ADDITIONAL PRECIP, WHICH THE MDLS DEVELOP DIFFERENTLY. THE ECMWF TRIES TO DEVELOP SOME FROM AN AREA OF LOW PRES WHICH TAKES SHAPE FROM SOME SRN STREAM ENERGY OVER THE SERN STATES AND MOVES NEWD. THE GFS HAS SOME NRN STREAM AND SRN STREAM ENERGY AND PSBLY ANOTHER WK FROPA. AGAIN, FOR NOW WILL JUST CARRY SOME LOW POPS. TEMPS WILL GENLY AVERAGE NR NRML, EXCEPT FOR SUN IN THE COLD ADVECTION BEHIND THE STRONG FROPA, WHERE TEMPS WILL AVERAGE MUCH BELOW NRML.
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&& .AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
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THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. THROUGH 12Z...MVFR AND IFR CIGS GRADU LOWER TO IFR MOST OF THE AREA. SCT SHOWERS IN NJ AND VCNTY KRDG/KMPO. LIGHT NE WIND. TODAY AFTER 12Z...MVFR/IFR CIGS LINGER THIS MORNING BEFORE BECOMING VFR AROUND MIDDAY TO EARLY AFTERNOON FOR THE TAF SITES. AN ISOLATED TO SCATTERED SHOWER REMAINS POSSIBLE THROUGH THE MORNING. NORTHEASTERLY WINDS ARE EXPECTED, MOSTLY IN THE 8 TO 10 KNOT RANGE. TONIGHT...MVFR OR IFR CIGS REDEVELOP LATER ON WITH LOW POSSIBLY PATCHY 1-3MI FOG AFTER 06Z/2. LIGHT NORTH WIND. OUTLOOK... THU...MVFR CONDS PSBL EARLY OTHERWISE VFR. PSBL LINGERING SHRA EARLY AT MIV/ACY, OTHERWISE DRY. MDT TO HIGH CONFIDENCE. FRI..VFR ERLY. PSBL MVFR W LATE. RAIN CHCS LATE W. MDT CONFIDENCE. FRI NIGHT...MVFR/IFR WITH INCREASING RAIN CHCS FROM W TO E BY DAYBREAK. RAIN CUD BE HEAVY AT TIMES, WITH APPROACHING CDFNT. MDT CONFIDENCE, THOUGH LOW TO MDT ON FRONTAL POSN. SAT...MVFR/IFR EARLY IN RAIN, HEAVY AT TIMES...INCREASING TO VFR. RAIN ENDING FROM W TO E DURG THE MRNG/AFTN. CFP LATE MRNG ERLY AFTN FROM W TO E AND WSHFT FROM SE TO WNW. MDT CONFIDENCE.
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&& .MARINE...
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TWO WEEKS AFTER RESTORATION OF A LENGTHY BUOY 44065 OUTAGE...DATA TRANSMISSION TOPPED AT 4PM THIS PAST TUESDAY AFTERNOON. NDBC HAS BEEN CONTACTED AND THEY WILL LET US KNOW WHAT THE PROBLEM IS. IN THE MEANTIME...MARGINAL SCA CONDITIONS ARE FCST FOR THE NNJ WATERS TODAY. WE DONT REALLY KNOW WHAT THE SEAS ARE DOING OFF THE NNJ COAST. NO EXPANSION OF THE SCA FOR THE REMAINDER OF THE WATERS IN OUR 330 AM FCST. BASICALLY NE FLOW CONTINUES THROUGH TONIGHT WITH MAX GUSTS AROUND 20 KT. SEAS BUILD TO NEAR 5 FT NORTHERN WATERS...NEAR 4 FT SOUTHERN WATERS AND GENERALLY 1-2 FT DELAWARE BAY. OUTLOOK... THU...ELY FLOW WILL PERSIST AND THERE COULD BE SCA CONDS ONCE AGAIN, WITH A BETTER CHANCE OVER THE NRN WATERS. HOWEVER, THU IS A MARGINAL DAY AND THE LATEST GUID INDICATES WE MAY FALL JUST SHORT. THU NIGHT INTO FRI...SCA WILL LIKELY BE NEEDED AT SOME POINT DURG THIS PD AS SEAS INCREASE AHEAD OF AN APPROACHING CDFNT. SAT...STRONG CFP. WSFHT TO NW OR WNW. SEAS WILL INCREASE FURTHER AND SCA WILL CONTINUE. BEST CHC FOR SCA WIND DURG THIS TIME FRAME.
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&& .PHI WATCHES/WARNINGS/ADVISORIES...
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PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 6 AM EDT THURSDAY FOR ANZ450>452.
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&& $$ SYNOPSIS...NIERENBERG NEAR TERM...DRAG SHORT TERM...DRAG LONG TERM...NIERENBERG AVIATION...DRAG/NIERENBERG MARINE...DRAG/NIERENBERG

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