657 FXUS61 KPHI 130128 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 928 PM EDT Tue Mar 12 2019 .SYNOPSIS... High pressure over the Ohio Valley this evening will move east and crest over the Middle Atlantic region Wednesday. The high will then move offshore through Thursday. Strong low pressure will develop across the Plains states and then move across the Great Lakes and then into Canada by Friday. Its associated fronts will affect our region later Thursday and through Friday night. High pressure will once again return for the weekend and into early next week. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... No changes to the forecast needed tonight other than minor hourly adjustments. A very nice, cool night in store as high pressure centers itself across the area overnight. We are anticipating a clear sky, and a light and variable wind for tonight. Low temperatures are forecast to be mostly in the 20s. Readings should not drop below 30 in urban areas and along the immediate coast. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... The center of high pressure is forecast to slide off the coast on Wednesday. A light and variable wind is expected to settle into the south and southwest around 5 to 10 MPH in the afternoon. Wednesday will feature a good deal of sunshine. However, we are anticipating and increase in mid level clouds from the west late in the day. Maximum temperatures should be mostly in the lower 50s in our region. Readings are not forecast to get above the middle and upper 40s in the elevated terrain up north. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... High pressure will be offshore Wednesday night while low pressure moves across the Great Lakes. A warmer and more humid southerly flow will become established across our area. Increasing clouds will occur through Thursday with milder temperatures also expected. Lows Wed night will hold in the 30s in most areas and highs Thursday will climb above normal with mid 50s (north) and upper 50s to low 60s (south). WInds will become southerly Thu at 10 to 15 mph. The deep low across the Great Lakes will continue to move NE into Canada later Fri and into Saturday. This will continue to produce a mild and humid flow across the area. Showers will develop Thu night and continue through Friday night. Most of the models show the same general scenario, so confid in the fcst is good. Pops are in the high likely/low categorical range. We will continue the chc for thunder also with some elevated CAPE indicated on the soundings. Overall, around 1/2 inch of QPF expected with some local higher amts N/W. Temperatures will drop back near normal for the weekend and remain that way into next week, as an upper trough remain across the region. Mostly high pressure is indicated, so a dry fcst is expected. One weak upper disturbance may bring widely scattered showers Monday afternoon and night, so some slight chc pops are in the fcst for those periods. && .AVIATION /02Z WEDNESDAY THROUGH SUNDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...VFR/SKC. NW winds 10 kt or less, becoming LGT/VRB this evening. High confidence. Wednesday...VFR. FEW250, lowering to SCT150 in the afternoon. LGT/VRB winds in the morning, becoming south less than 10 kt in the afternoon. High confidence. Outlook... Wed night thru Thu...VFR. Increasing clouds Thu. Light winds Wed night then Srly winds 10 to 15 knots developing Thu afternoon. Thu night thru Fri night...Restrictions expected with frequent showers and a chc for a tstm Fri. Lower CIGS/VSBYS expected at times. Mostly S to SW winds 10-15 knots but wind becoming W/NW Fri night. Sat thru Sun...Mostly VFR. W/NW winds much of the time. && .MARINE... High pressure approaching from the west will pass across the coastal waters of New Jersey and Delaware on Wednesday. The gusty northwest wind early this evening should become north 5 to 10 knots overnight. The wind direction is expected to veer to the south on Wednesday. Outlook... Wed night and Thu...Sub-SCA with fair weather. Thu night thru Fri night...SCA expected. Showers with a chc of a tstm Fri. Sat thru Sat night...SCA. Fair. Sun...Sub-SCA. Fair. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None. && $$ Synopsis...O'Hara Near Term...Iovino/Robertson Short Term...Iovino Long Term...O'Hara Aviation...MPS/O'Hara Marine...Iovino/O'Hara