Area Forecast Discussion
Issued by NWS Sterling, VA

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309 FXUS61 KLWX 270743 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 343 AM EDT Thu Oct 27 2016 .SYNOPSIS...A cold front will cross the area this evening. High pressure then builds over the area tonight through Friday night. A secondary cold front crosses the area Sunday afternoon. High pressure builds again Sunday night into the middle of next week. && .NEAR TERM /THROUGH TONIGHT/...Low pressure is located over northern IN/OH this morning. A warm front is across the Ohio Valley while high pressure continues to move off the Mid-Atlantic coast early this morning. Strong warm air advection aloft is occurring this morning across the Ohio Valley and NY/PA. Most of the precipitation is in vicinity of the nose of warm air. Although the best forcing is further north...showers are expected across the Mid-Atlantic region today. High pressure will continue to move eastward and the sfc warm front will move through the Mid-Atlantic region by afternoon. This will cause temps to rise into the U50s across the north and low/mid 60s further south. Winds will increase this afternoon as the pressure gradient tightens ahead of an advancing cold front. S winds 10-15 mph with gusts up to 25mph are expected today. The cold front will cross the Mid-Atlantic region late this afternoon/early evening from west to east. Showers are likely along and ahead of the front. Steepening lapse rates may produce some instability today. A stronger shower or weak thunderstorm can not be ruled out mainly along the front. Rainfall amounts will average 0.1 to 0.25 with the highest amounts near the MD/PA border. The cold front should be east of the region tonight and NW winds will begin to advect in cool and dry conditions. Winds are expected to increase after midnight tonight with 10-20mph with gusts up to 30mph. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...High pressure moves into the region Friday however a pressure gradient will still be present. Breezy conditions will continue through most of the afternoon with NW winds 10-15mph and gusts up to 25 mph. Temps will range from the U50s/L60s north to mid 60s south. High pressure moves briefly over head Friday night before shifting south by Saturday. Partly sunny conditions expected Saturday with temps climbing into the 70s in most locations. A cold front approaches the region from the north Sat night. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/...Recent runs have shown frontal passage for Sun has been pushed back until late in the day. This will allow for temps to climb into the low 80s across Charlottesville and Fredericksburg with mid to upper 70s elsewhere. Scattered showers will be possible along and behind the front over northern and northwestern areas Sun afternoon with precip chances decreasing as you move south. Front pushes south of the area after 06Z Mon with showers ending. Cooler wx Mon as high pres builds in. Ampliflying mid-upper level ridge over the southeast U.S. into the mid Atlc states early next week will help rebound temps quickly with mid 70s to low 80s expected. Rain chances may increase toward the end of next week. && .AVIATION /07Z THURSDAY THROUGH MONDAY/...MVFR cigs possible at MRB/IAD 11-14Z as scattered showers form across southern PA/northern MD this morning. VFR conditions expected elsewhere as a warm front moves northward today. S winds will increase by this afternoon with gusts up to 25 kts expected. A cold front will cross the terminals from west to east this afternoon and evening. Winds will likely diminish slightly after the frontal passage, however, NW winds will increase late tonight through Friday. Gusts up to 25 kts can not be ruled out after midnight tonight. Winds will diminish late Friday afternoon. A cdfnt will cross the area Sun afternoon with winds shifting to NW and then N Sun night. && .MARINE...Southerly winds will increase ahead of a cold front this morning. SCA begins at this morning for the southern MD waters then expands at 10am for all waters with southerly channeling of 20 to 25 knots. Likely showers late Thursday afternoon/evening associated with the cold front. Strong gusts and special marine warnings possible with the showers. Wind shifts W then NW behind the cold front Thursday night with gusts around 25 kt into Friday morning. Tranquil Friday evening under high pressure. SCA is in effect for all waters through Friday afternoon. Southwesterly winds ahead of an approaching cold front Saturday will likely result in Small Craft Advisory level wind gusts over the waters. Small craft advzy conditions possible Sun into Mon behind fropa. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory from 10 AM this morning to 6 PM EDT Friday for ANZ530>532-535-536-538>542. Small Craft Advisory from 6 AM this morning to 6 PM EDT Friday for ANZ533-534-537-543. && $$ SYNOPSIS...LFR NEAR TERM...HSK SHORT TERM...HSK LONG TERM...LFR AVIATION...HSK/LFR MARINE...HSK/LFR is the U.S. government's official web portal to all federal, state and local government web resources and services.