Area Forecast Discussion
Issued by NWS Sterling, VA

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984 FXUS61 KLWX 261937 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 337 PM EDT Tue Jul 26 2016 .SYNOPSIS... A front will remain stationary across the Mid-Atlantic region through the middle of the week. Low pressure will cross the region Thursday night into Friday. Another cold front will approach the area early next week. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... Remnants of front is barely noticeable in observations this afternoon. However, mesoanalysis depicts a gradient in CAPE across the area with the highest to the south. This is where thunderstorms are expected to be most concentrated during the afternoon and evening hours. Coverage may increase toward evening as a weak shortwave approaches. Shear and lapse rates are modest, but a few stronger pulse or multicell storms are possible with strong wind gusts being the primary threat. Although the greatest storm risk will subside in the evening, can`t rule out a storm or two overnight as the boundary lingers in the area. Overnight lows will again be muggy in the 70s east of the mountains. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/... The front may move a little to the south Wednesday, but some storms will still be possible over southern portions of the area. The front will begin to lift back north Thursday and Thursday night as a surface low approaches. Flow will also strengthen aloft attendant to a short wave trough. There is still some spread in guidance, but there could be a severe and heavy rain threat depending on the low track. Temperatures will likely remain above normal. && .LONG TERM /FRIDAY THROUGH TUESDAY/... While timing differences remain, overall depiction among long-term guidance is for an unsettled weather pattern this weekend, as multiple impulses rotate through broad cyclonic flow aloft. This will help suppress temperatures back closer to normal, which will be a welcome relief after the elevated temperatures of earlier this week. However, even though we have been relatively dry across the area, multiple rounds of rainfall could create some Hydro issues, as moisture throughout the column will be plentiful. Cold front approaches the area Sunday into Monday and is then forecast to hang up just south of the area Monday and Tuesday. Current forecast has our area on the "cooler" (M/U80s) and drier side of the front Monday and Tuesday...with best precipitation chances generally in the southern portion of the forecast area. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... Storms will be most likely near CHO through evening, although a few showers/storms may be near the DC sites as well. Cloud cover will likely preclude much fog tonight. CHO will be the focus for scattered storms again on Wednesday. Low pressure crossing the area late Thursday may bring more widespread storms and rain with more prolonged sub-VFR conditions. Risk of showers and thunderstorms continues over the weekend, with warm and moist atmosphere remaining and several impulses moving through the upper-level flow. && .MARINE... The main threat through Thursday night will come from thunderstorms producing gusty winds. This threat will greatest over the souther waters. Gradient winds will likely remain below 15 kt as a weak front is stalled across the area. Gradient winds remain sub-SCA Friday through the weekend, though higher winds and waves can be expected near thunderstorms. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...Heat Advisory until 8 PM EDT this evening for MDZ016>018. VA...Heat Advisory until 8 PM EDT this evening for VAZ036-037-050- 055>057. WV...None. MARINE...None. && $$ SYNOPSIS...ADS NEAR TERM...ADS SHORT TERM...ADS LONG TERM...MSE AVIATION...ADS/MSE MARINE...ADS/MSE is the U.S. government's official web portal to all federal, state and local government web resources and services.