Area Forecast Discussion
Issued by NWS Sterling, VA

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000 FXUS61 KLWX 261854 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 254 PM EDT Mon Jun 26 2017 .SYNOPSIS...A sharp upper level trough will move across the region on Tuesday. High pressure builds over the area Wednesday and moves offshore Thursday. && .NEAR TERM /THROUGH TONIGHT/...Quiet conditions tonight under weak high pressure. Some high clouds will start moving in late tonight and early Tue. Cool with lows in the 50s except mid 60s in city centers. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...A sharp upper level trough will move across the area late tomorrow. Strong height falls will provide large scale forcing for showers and thunderstorms to develop. Biggest limiting factor is lack of low-level moisture and weak instability with CAPE values progged at less than 250 J/kg. Best coverage of showers will be east of the Blue Ridge mtns where instability will be higher. Showers will only produce very light rainfall due to relatively high base clouds and a ton of mid-level dry air. Gusty winds and small hail may be possible due to inverted-V soundings and very cool temps aloft for this time of the year. -20C 500 mb temps are progged which is near record low for late Jun. Trough axis moves east Tue evening with rapid clearing. High pressure builds for Wed with tranquil weather. && .LONG TERM /THURSDAY THROUGH MONDAY/... High pressure will be in control Thursday through Thursday night, bringing dry conditions and above normal temperatures. There could be a stray shower along the Mason-Dixon region Thursday night. As high pressure moves over the western Atlantic, warmer temperatures and increasing chances of showers and thunderstorms will develop Friday through Sunday. The best chance for showers and storms will be Saturday and Sunday. A second area of high pressure will build into the region Monday, bringing more seasonable temperatures and dry conditions. && .AVIATION /19Z MONDAY THROUGH SATURDAY/...VFR conditions next 72 hrs. Widely scattered or scattered showers and t-storms are expected tomorrow. No restrictions are anticipated. High pressure builds for Wed. Vfr conditions Thursday and Thursday night. Winds southwest 10 knots Thursday and Thursday night. Mvfr to ifr conditions are possible with showers and storms Friday and Friday night. Winds southwest 5 to 10 knots Friday and Friday night. && .MARINE...Srly winds expected to strengthen tonight with SCA conditions. Winds will diminish toward morning. Very marginal SCA conditions possible tomorrow, but not enough confidence to issue SCA, however, gusty winds in showers or t-storms may require MWSs or even SMWs due to very dry environment and potential for deep mixing. Small craft advisories may be needed Thursday and Thursday night. Winds southwest 10 to 15 knots gusts 20 knots. No marine hazards expected Friday and Friday night. Winds southwest around 10 knots. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...Small Craft Advisory from 9 PM this evening to 2 AM EDT Tuesday for ANZ531>533-538>541. Small Craft Advisory from 9 PM this evening to 4 AM EDT Tuesday for ANZ534-537-543. && $$ SYNOPSIS...LFR NEAR TERM...LFR SHORT TERM...LFR LONG TERM...KLW AVIATION...LFR/KLW MARINE...LFR/KLW is the U.S. government's official web portal to all federal, state and local government web resources and services.