Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 140801 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 401 AM EDT Wed Mar 14 2018 .SYNOPSIS... Strong low pressure will remain stalled over the Canadian Maritimes into Atlantic Canada through Saturday. Meanwhile high pressure will extend south from Canada across the Great Lakes and Ohio Valley, maintaining a relatively cold northwest flow across the mid- Atlantic region into the weekend. Another coastal storm may develop in the early to middle part of next week, but as of now its track, timing and intensity are uncertain. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Good morning! Snow flurries and snow showers have already started moving southeast into the I80 region as the axis of the cold crosses our area today. Snow squalls should develop this afternoon. Isolated 3-4" amounts are possible in the Poconos by nightfall where the snow ratios are 17 to 1. Further se along I95 this afternoon, snow showers may begin as mix of rain/snow but quickly become all snow but above freezing temps should prevent accumulation I95 sewd unless an organized band develops that lasts 45 minutes. An SPS will issue by 5 AM to highlight the potential adverse impact. Otherwise westerly winds this morning will increase markedly this afternoon as deeper momentum transfer develops in response to steeping lapse rates. Gusts 30-40 mph possible mid and late afternoon. Otherwise, the forecast basis was a 50 50 blend of GFS/NAM MOS and tended to run a little colder than the max temp blend, responding to the colder ECMWF 2m temps, and considerable cloud cover that will limit reaching the potential -10C 850 temp. Max temps 10-12F below normal. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM THURSDAY/... Considerable cloud cover early with a brisk west wind...gusty 20-30 MPH and scattered flurries and snow showers still offering the potential for further accumulation here and there nw of I95. Clearing late with winds diminishing as well. Again the forecast basis was a 50 50 blend of the GFS/NAM MOS. Min temps up to 7 degrees below normal. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Thursday through Friday... The area remains under the influence of upper level trough with a NW flow predominating through this period. Another shortwave aloft coupled with a wave at the surface will move through Thursday afternoon producing some scattered showers which could be mixed with or fall as some wet snow showers over northern areas through the southern Poconos and NW NJ. Winds will also be gusty once again due as low level lapse rates will be steep so stronger winds aloft will be able to easily mix down. Highs will range from the mid 30s to near 40 over the southern Poconos and NW NJ and will be in the 40s elsewhere. For Thursday night and Friday, gusty and colder weather will follow as the pressure gradient remains strong behind the stalled low over the Canadian Maritimes with high pressure over the Great Lakes. However expect mainly dry weather through this period. Lows Thursday night will be mainly in the 20s except near 30 over the Delmarva, coastal NJ and the Philly metro area. Highs Friday will range from the upper 20s to low 30s across the southern Poconos and NW NJ to the mid 30s to low 40s elsewhere. Considerable cloudiness will persist Friday across the north with partly to mostly sunny skies south. Friday night through Tuesday... In the big picture, the persistent pattern we`ve been in remains in place with troughiness persisting over the NE CONUS into eastern Canada with ridging over the north Atlantic. This will help keep conditions relatively cool with additional chances for storminess heading into next week. However for the weekend, high pressure will predominate bringing dry weather. There will be some high cloudiness around from time to time as a weak wave passes by to the south. Otherwise, expect sunshine with seasonably cool temperatures Saturday giving way to milder temps for Sunday with highs likely cracking 50 for roughly the southern half of the forecast area with 40s farther north. High pressure with fair weather persists into early next week however by next Tuesday indications are another coastal storm may develop along the east coast potentially bringing the area more rain or snow. However at this point it is too early to be confident in the system`s track and intensity and its resulting impacts over the area. && .AVIATION /08Z WEDNESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Today...VFR cigs develops aoa 4000 ft. Scattered snow showers will impact KABE/KRDG, and scattered rain and/or snow showers may briefly impact KTTN/KPNE/KPHL. Best chances at KABE/KRDG. Brief IFR conditions possible. West winds increase to 15-20 KT with 25-35 kt gusts developing this afternoon. Tonight...VFR cigs aoa 4000 ft clear late but not after a chance of snow showers vcnty KABE this evening. West winds gusty 22-32 kt this evening, diminish late. Outlook... Thursday...Mostly VFR. Occasional MVFR possible in snow or rain showers during the day. Westerly winds gusting to 20-25 knots. Moderate confidence. Thursday night - Friday...VFR. NW winds gusting 20-25 knots Friday. Saturday and Sunday...VFR. && .MARINE... GLW issued and is the primary message with SCA conds leading up to the strongest westerly gusts of 35-45 kt this evening. Winds slowly subside toward dawn Thursday. Used NWPS waves. Outlook... Winds diminish below Gale levels by Thursday afternoon however expect winds near or above SCA levels to continue through Friday. Seas will generally be around 3 to 4 feet over the ocean waters and 2 to 3 feet over the Delaware Bay during this time period. Winds diminish by later Friday night and should be sub SCA levels Saturday through Sunday. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...Gale Warning from 2 PM this afternoon to noon EDT Thursday for ANZ450>453. Gale Warning from 2 PM this afternoon to 6 AM EDT Thursday for ANZ430-431-454-455. && $$ Synopsis...Fitzsimmons Near Term...Drag 401 Short Term...Drag 401 Long Term...Fitzsimmons Aviation...Drag/Fitzsimmons 401 Marine...Drag/Fitzsimmons 401 is the U.S. government's official web portal to all federal, state and local government web resources and services.