Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KPHI 200326 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 1126 PM EDT TUE MAY 19 2015 .SYNOPSIS...
-- Changed Discussion --
A COLD FRONT LATE THIS EVENING FROM NEW YORK CITY TO WASHINGTON DC WILL MOVE OFF THE COASTS BY DAWN. HIGH PRESSURE IS FORECAST TO FOLLOW FOR WEDNESDAY INTO WEDNESDAY NIGHT. WEAK LOW PRESSURE IS EXPECTED TO BE LOCATED OVER NORTH CAROLINA ON THURSDAY BEFORE IT MOVES OUT TO SEA ON THURSDAY NIGHT. A COLD FRONT FROM THE NORTHWEST IS ANTICIPATED TO ARRIVE ON FRIDAY EVENING WITH HIGH PRESSURE FORECAST TO BUILD ACROSS OUR REGION IN ITS WAKE FOR SATURDAY. A WARM FRONT IS EXPECTED TO APPROACH FROM THE SOUTHWEST ON SUNDAY AND MONDAY, AS A COLD FRONT PUSHES DOWN FROM THE NORTH AND NORTHEAST. ANOTHER FRONTAL BOUNDARY MAY MOVE TOWARD OUR REGION FROM THE NORTHWEST ON TUESDAY.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH WEDNESDAY/...
-- Changed Discussion --
CFP IN PROGRESS WITH SOME GUSTY NW WINDS TO 20 MPH AND RAPIDLY LOWERING DEWPOINTS BY MORNING. REFRESHING AIR COMING. WEDNESDAY...BRIGHT SUNSHINE WITH AN FEW SC IN THE AFTN. MAX TEMPS ALMOST 15 DEGREES COOLER THAN THE VALUES OF TUESDAY AND DAYTIME MAX TEMPS ABOUT 5 DEGREES BELOW NORMAL! GUSTY NORTHWEST WINDS 20 TO 25 MPH.
-- End Changed Discussion --
&& .SHORT TERM /WEDNESDAY NIGHT/...
-- Changed Discussion --
HIGH PRESSURE IS FORECAST TO CONTINUE INFLUENCING OUR WEATHER INTO WEDNESDAY NIGHT. HOWEVER, HIGH AND MID LEVEL CLOUDS WILL BE ON THE INCREASE AFTER MIDNIGHT. LOW TEMPERATURES ARE ANTICIPATED TO BE MAINLY IN THE 40S AND LOWER 50S IN OUR REGION WITH A FEW READINGS IN THE UPPER 30S IN THE FAR NORTH.
-- End Changed Discussion --
&& .LONG TERM /THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --
THE MODEL GUIDANCE IS COMING INTO BETTER AGREEMENT REGARDING THURSDAY`S WEAK LOW IN NORTH CAROLINA AND ITS IMPACTS ON OUR WEATHER. IT APPEARS AS THOUGH MID LEVEL CLOUDS WILL BE OVERHEAD FOR MUCH OF THURSDAY INTO THURSDAY EVENING. A DECK OF STRATOCUMULUS IS ANTICIPATED TO EXPAND OVER OUR SOUTHERN COUNTIES ON THURSDAY BEFORE CLEARING GRADUALLY FROM THE NORTHWEST ON THURSDAY NIGHT. ALSO, RAIN IS ANTICIPATED TO AFFECT NORTHEASTERN MARYLAND, DELAWARE AND SOUTHERN NEW JERSEY. THE FORECAST IMPACTS ON THE NORTHERN EDGE OF THE SYSTEM MAY SHIFT A LITTLE AS WE GET CLOSER TO THE EVENT. A MID LEVEL SHORT WAVE TROUGH IS FORECAST TO APPROACH FROM THE WEST ON THURSDAY NIGHT AND IT SHOULD PASS OVERHEAD EARLY ON FRIDAY. A SECOND SHORT WAVE IS EXPECTED ON FRIDAY NIGHT. IT SHOULD BE PRECEDED BY A COLD FRONTAL PASSAGE IN OUR REGION ON FRIDAY EVENING. THE SYSTEM SHOULD NOT HAVE MUCH MOISTURE ASSOCIATED WITH IT, SO WE WILL FORECAST FEW CLOUDS AND NO RAINFALL. SURFACE HIGH PRESSURE WILL BUILD INTO OUR REGION ON FRIDAY NIGHT AND SATURDAY. THE CENTER OF THE HIGH IS EXPECTED TO PASS OFF THE COAST LATE ON SATURDAY. THE AIR MASS SHOULD BRING OUR FORECAST AREA DRY WEATHER CONDITIONS ALONG WITH SLIGHTLY BELOW NORMAL TEMPERATURES. WARMTH AND MOISTURE WILL LIKELY BE ON THE INCREASE ON THE BACK SIDE OF THE HIGH AS WE GET INTO SUNDAY AND MONDAY. MEANWHILE, A BACK DOOR COLD FRONT MAY PUSH DOWN FROM THE NORTH AND NORTHEAST ON SUNDAY NIGHT AND MONDAY. WE ARE ANTICIPATING AN INCREASE IN CLOUD COVER FROM THE SOUTHWEST IN THE DEVELOPING ISENTROPIC LIFT. ALSO, THERE MAY BE SOME STRATUS IN THE WAKE OF THE BACK DOOR COLD FRONT. THE TIMING AND PROGRESSION OF BOTH BOUNDARIES REMAINS A LOW CONFIDENCE FORECAST AT THIS POINT, FIVE AND SIX DAYS REMOVED. HOWEVER, WE WILL INDICATE THE INCREASE IN CLOUD COVER ALONG WITH A CHANCE OF SHOWERS ON SUNDAY NIGHT AND MONDAY MORNING, AND A CHANCE OF SHOWERS AND THUNDERSTORMS ON MONDAY AFTERNOON. THE AXIS OF A MID LEVEL RIDGE IS FORECAST TO PASS OVERHEAD ON MONDAY NIGHT. ANOTHER FRONTAL BOUNDARY MAY APPROACH FROM THE NORTHWEST ON TUESDAY, SO WE WILL CONTINUE TO MENTION THE POTENTIAL FOR SOME CLOUDS AND A CHANCE OF SHOWERS AND AFTERNOON THUNDERSTORMS.
-- End Changed Discussion --
&& .AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. OVERNIGHT...WSHIFT FM SW TO NW WITH GUSTS AROUND 20 KT AND GENERALLY CLEAR SKY. AFTER 12Z WEDNESDAY...VFR CLEAR WITH SCT SC DURING THE AFTN AOA 4000 FT. NW WIND GUSTS 20-25 KT. WEDNESDAY NIGHT...VFR CLEAR TO START THEN CIGS AOA 10000 FT ARRIVING AFTER 06Z. LIGHT WIND. OUTLOOK... THURSDAY AND THURSDAY NIGHT...MAINLY VFR. A CHANCE OF RAIN FROM KILG, KMIV AND KACY SOUTHWARD. FRIDAY THROUGH SUNDAY...MAINLY VFR.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
OVERNIGHT...THE COLD FRONT PASSES WITH A WSHIFT FROM SW TO NW AND GUSTY 20 KT. GUSTS COULD REACH 25 KT OVER THE NRN WATERS AFTER 3 AM WEDNESDAY. SEAS SHOULD BE NO HIGHER THAN 4 FEET. WEDNESDAY...NORTHWEST WINDS GUSTY TO NEAR 20 KT. WEDNESDAY NIGHT...NORTHWEST WINDS GUSTY 20 KT TURN N-NE AND DIMINISH TO LESS THAN 15 KT BY THURSDAY MORNING. OUTLOOK... THURSDAY THROUGH SUNDAY...NO MARINE HEADLINES ARE ANTICIPATED.
-- End Changed Discussion --
&& .FIRE WEATHER...
-- Changed Discussion --
WEDNESDAY...WE`LL SEE WINDS GUSTING TO 25 MPH AND DRY FINE FUELS ACROSS PORTIONS OF THE REGION, BUT MINIMUM RH`S ARE FORECAST TO BE IN THE 30-40% RANGE. ALSO, WIND GUSTS MAY BE AROUND 20 MPH FROM THE NORTHWEST ON FRIDAY AFTERNOON. RELATIVE HUMIDITY VALUES MAY FALL INTO THE 30 TO 35 PERCENT RANGE AT THAT TIME IN MUCH OF OUR REGION.
-- End Changed Discussion --
&& .CLIMATE...
-- Changed Discussion --
**TOP 10 WARMEST MAY APPEARS LIKELY IN PTNS OF THE FORECAST AREA** THE FIRST 19 DAYS OF MAY IN OUR FORECAST AREA ARE AVERAGING WITHIN ABOUT 1/2 DEGREE OF 7 DEGREES ABOVE NORMAL. BASED ON THE ENSEMBLE AND FORECAST DETERMINISTICALLY CONSERVATIVE INCLUDING OUR 330 PM MAY 19 PROJECTIONS THROUGH THE 26TH AND THEN THE CONSERVATIVE FTPRHA THEREAFTER THROUGH THE 29TH AND NORMAL THE 30TH AND 31ST...OUTLOOKS A TOP 10 WARMEST MAY ON RECORD. FOR PHILADELPHIA...POR TO 1874. PROJECTING AN AVG TEMPS OF 68.7 OR NEARLY 5 DEGREES ABOVE NORMAL (4.8) AND 3RD WARMEST ON RECORD. WARMEST WAS 70.8 IN 1991. THEN 69.2 2004. FOR ALLENTOWN...POR TO 1922. PROJECTING 65.0 OR 5.1 DEGREES ABOVE NORMAL AND 8TH WARMEST ON RECORD. WARMEST WAS 67.2 IN 1991.
-- End Changed Discussion --
&& .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...IOVINO NEAR TERM...DRAG/HEAVENER/KRUZDLO 1127P SHORT TERM...DRAG/KRUZDLO 1127P LONG TERM...IOVINO AVIATION...DRAG/IOVINO/KRUZDLO 1127P MARINE...DRAG/IOVINO/KRUZDLO 1127P FIRE WEATHER...

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.