Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 200032 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 832 PM EDT Tue Sep 19 2017 .SYNOPSIS... A ridge of high pressure will remain over the eastern United States through early next week. Meanwhile, Hurricane Jose is expected to track north off the Mid Atlantic coast through Wednesday. Refer to the National Hurricane Center`s website for the latest on Jose. && .NEAR TERM /UNTIL 7 AM WEDNESDAY MORNING/... A ridge of high pressure remains overhead this evening as Hurricane Jose gradually moves northeastward offshore of the Mid-Atlantic coastline. Western extent of the cloud shield from Jose reaches to about the I-95 corridor this evening, and that should progress eastward during the overnight hours. A few rain showers in the far outer band also remain near the Chesapeake, but those too should diminish. With mostly clear skies and diminishing winds, patchy fog will likely develop again tonight into early Wednesday morning, mainly west of the metros. The pressure gradient from Jose should keep enough wind in the boundary layer to prevent fog from developing in points east. Lows overnight will range from the upper 50s to upper 60s, locally 70F in the urban centers. && .SHORT TERM /7 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... An upper-level ridge will remain over the area...but a weak disturbance will approach from the west. A northwest flow behind Jose will allow for sunshine and it will be unseasonably warm for this time of year due to subsidence associated with the upper-level ridge. Max temps will be in the mid to upper 80s across most locations. A few popup showers are possible later Wednesday afternoon and evening across the Potomac Highlands into central Virginia where there will be a little instability closer to the weak upper- level disturbance. However...coverage will be isolated to widely scattered due to the lack of a strong lifting mechanism. High pressure both at the surface and aloft will continue to build overhead Wednesday night through Thursday night. Dry warm conditions are expected during this time. Areas of fog are likely during the overnight and morning hours. && .LONG TERM /FRIDAY THROUGH TUESDAY/... Mainly dry conditions expected in the long term period as upper level ridge/surface high pressure continues over our area Friday into Tuesday. Some showers over the ridges cannot be ruled out, but looking dry over most of our CWA. High temperatures will be in the mid 80s, around 10 degrees higher than normal. Remnants of Jose might be lingering off of the Mid- Atlantic/New England coast, away from us, and Maria could be somewhere in the west Atlantic, but it is too early to tell. Check out the National Hurricane Center`s website:, for additional information in both Jose and Maria. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... VFR conditions are expected through the remainder of the evening. Patchy fog will then develop overnight into Wednesday morning, with greatest risk for IFR at CHO and MRB. Little impact expected at other sites. High pressure will remain over the terminals for later Wednesday through Thursday night. Areas of fog are possible during the overnight and morning hours. VFR conditions expected Friday into Sunday with high pressure over our area. && .MARINE... Jose will continue to move north well offshore, moving away from the area tonight through Wednesday. Breezy conditions with gusts around 20 to 25 knots have occurred this evening...with the strongest winds over the southern Maryland Chesapeake Bay and lower Tidal Potomac. Winds will remain near SCA criteria for portions of the waters into Wednesday morning. Therefore the Small Craft Advisory remains in effect for tonight into Wednesday across the middle portion of the Bay and the lower Tidal Potomac River as north to northwest winds channel. Northwest winds will continue Wednesday afternoon. A few gusts around 20 knots cannot be ruled out...but latest forecast has gusts capped at 15 knots due to a weaker gradient as Jose moves away. High pressure will build overhead for Wednesday night through Thursday night. No small craft advisory expected between Friday and Sunday due to low wind speeds over our area. && .TIDES/COASTAL FLOODING... A Coastal Flood Advisory remains in effect for Straits Point in St. Marys county through tonight, and will likely need to be extended. Anomalies elsewhere have risen markedly over the past couple of hours as northerly winds abate, so Coastal Flood Advisories may be needed beginning late tonight into Wednesday and Thursday. Moderate flooding cannot be ruled out at Straits Point Wednesday into Thursday as well. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Coastal Flood Advisory until 6 AM EDT Wednesday for MDZ017. VA...None. WV...None. MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ532-533- 540-541. Small Craft Advisory until 11 AM EDT Wednesday for ANZ534-537- 543. && $$ SYNOPSIS...BJL NEAR TERM...BJL/MM SHORT TERM...BJL LONG TERM...IMR AVIATION...BJL/MM/IMR MARINE...BJL/MM/IMR TIDES/COASTAL FLOODING...BJL/MM is the U.S. government's official web portal to all federal, state and local government web resources and services.