Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 261358 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 958 AM EDT Wed Oct 26 2016 .SYNOPSIS... High pressure will remain over the region through tonight. A cold front will cross the area Thursday afternoon and evening. High pressure returns Friday and Friday night. A secondary cold front crosses the area this weekend with high pressure then into at least the middle of next week. && .NEAR TERM /THROUGH TONIGHT/... First freeze for IAD and BWI - please see climate section below. As of 9am, a 1038mb surface high is over northern Ontario with a surface ridge extending south to the central Mid-Atlantic. A 1013mb surface high is over IA with a warm front extending east to Cleveland. This warm front will extend east across PA through this evening and the low crosses the eastern Great Lakes through Thursday. The surface high pressure ridge drifts east today and a weak onshore flow beginning this afternoon. Max temps in the 50s and 40s in the mountains are expected. A warm front will move northward across the Ohio Valley region this afternoon and evening. High pressure in place across the Mid-Atlantic will keep the warm front from moving northward across the region, however, mid-high clouds will increase from west to east today and tonight in response to the warm front aloft. As moisture advects northward, showers are also possible, however, they should stay west and north of the Mid- Atlantic region as the associated low pressure system moves into the Great Lakes region by Thursday morning. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... Low pressure will move across Lake Erie and Lake Ontario Thursday while a cold front approaches the Mid-Atlantic region. The warm front will move through the region by Thursday afternoon. Clouds and showers are expected, however, the greatest forcing will be associated with the sfc low to our north. Rainfall amounts should not exceed a half inch into Thursday night. Winds will also increase ahead of the cold front Thursday afternoon and then behind the front Thursday evening. Winds at higher elevations will also be greater and gusts up to 35-40 mph will be possible during this time. The cold front moves to the east by Friday morning. Dry conditions are expected with the exception of showers tapering off across the Allegheny Front. High pressure will move overhead by Friday evening, however, it should quickly move east of the region by Saturday morning. && .LONG TERM /SATURDAY THROUGH TUESDAY/... Heights will be rising on Sat with H85 temps climbing to 13C close to the 90% percentile for late Oct. This will support warm temperatures well into the 70s and close to 80F in Charlottesville. Will need to watch Rh`s closely on Sat for an enhanced fire weather threat in case dewpoints do not recover as models suggest. A shortwave-trough and associated cdfnt cross the area Sun afternoon. A few showers appear possible along the Mason- Dixon line Sun morning. Temperatures could actually turn out to be warmer on Sun especially south of the Potomac River due to downslope flow. A brief cool down expected on Mon but temps expected to rebound again for the middle part of next week as ridge of high pressure amplifies over the southeast U.S. into the mid-Atlantic. Temperatures likely to rise well into the 70s and possibly low 80s middle of next week. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... VFR conditions are expected through tonight. Clouds will increase from west to east this afternoon. A cold front will approach the region Thursday and showers are possible. Cigs will lower with these showers and MVFR conditions are possible at this time. Winds will increase Thursday as well and gusts up to 20-30kts are possible in the afternoon and evening. VFR conditions are expected Friday-Friday night. VFR conditions expected Sat and Sun. && .MARINE... NE winds around 10kts expected on the waters today and tonight. Southerly winds will increase ahead of a cold front Thursday. The cold front will pass through Thursday evening and gusty northwest winds are expected behind the front overnight Thursday. A Small Craft Advisory is in effect Thursday through Thursday night. Winds may approach gale conditions mainly across the main channel of the Bay Thursday/Thursday night however confidence is low if a gale warning will be needed. Showers associated with the cold front will be gusty and may require special marine warnings, particularly Thursday evening. NW winds will continue Friday and SCA conditions are expected during this time. Winds should diminish Friday night. Small craft conditions are possible Sat afternoon and Sat night. && .CLIMATE... Baltimore-Washington International Thurgood Marshall Airport (BWI) near Baltimore MD dropped to 32 degrees this morning, marking the first time since April 10th that the temperature has dropped to freezing (low on April 10 was 26 degrees). Washington Dulles International Airport (IAD) in northern Virginia dropped to 30 degrees, which is the first time the temperature has fallen below freezing there since April 14th (when the low was 31 degrees). Ronald Reagan National Airport near Washington DC (DCA) was 41 degrees this morning. Its last day at or below freezing was 31 degrees on April 10. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory from 10 AM Thursday to 6 AM EDT Friday for ANZ530>532-535-536-538>542. Small Craft Advisory from 7 AM Thursday to 6 AM EDT Friday for ANZ533-534-537-543. && $$ SYNOPSIS...BAJ/LFR NEAR TERM...BAJ/HSK SHORT TERM...HSK LONG TERM...LFR AVIATION...BAJ/HSK/LFR MARINE...BAJ/HSK/LFR CLIMATE...DFH is the U.S. government's official web portal to all federal, state and local government web resources and services.