Area Forecast Discussion
Issued by NWS Sterling, VA
Issued by NWS Sterling, VA
656 FXUS61 KLWX 232347 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 747 PM EDT Thu Jul 23 2026 .WHAT HAS CHANGED... The latest guidance shows a slight uptick in rain shower chances a bit farther to the north Friday night. && .KEY MESSAGES... - 1) Below average temperatures and mainly dry conditions are expected into the weekend. - 2) Returning to a summer-like pattern next week. && .DISCUSSION... KEY MESSAGE 1...Below average temperatures and mainly dry conditions are expected into the weekend. Canadian high pressure will build from the upper GL today to NE by Fri night. The CAA on N`ly winds will support below normal highs in the upper 70s and lower 80s. Humidity will also be low, with Tds observed in the 40s today across the northern half of the CWA. Tonight will be the coolest for most areas with calm winds and mostly clear skies. Any rural areas could drop into the 50s, while the urban and bayshore remain in the mid 60s. Would not be surprised if colder valleys dropped into upper 40s. Fri will feature more mid and high level cloud cover. As the high becomes positioned to the NE, an inverted trough will develop along the Appalachian Mountains. This will help draw some moisture back nwrd from the stalled frontal zone across the SE-US. S/WVs in the NW flow could combine with the convergence in the surface trough to produce a few showers at times Fri afternoon through Sat night. This rain is most probable west of I-81, but a few showers across the srn tier can`t be ruled out depending on how the stationary front to our S buckles. While low temps will start creeping up in response to higher Tds, Sat high temps should remain below normal. KEY MESSAGE 2...Returning to a summer-like pattern next week. UL troffing will persist through much of next week over the NE US. S/WVs will move through the broad NW H5 flow with some guidance developing a cut-off low over NE towards the middle of next week. Regardless of UL evolution, a return to a summer-like pattern is favored with a notable increase in PWs/sfc RH. Heat builds gradually as well, but nothing near headline levels at this time. The increase in heat and moisture will increase instability and t-storm chances. Rain chances increase gradually each day through Tue (when there is some consensus a cdfnt could approach), but admittedly varies which day is highest between guidance. ML guidance highlights Tue as the highest day for SVR wx, though low probs exist almost daily. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... Little to no wx impacts are expected through Sat as high pressure passes by to the north. Winds become E`ly Fri and SE`ly Sat but remain light. Could have some low clouds at CHO Sat night. Low chance of t-storms Sun afternoon with an upper level disturbance, with the greatest chance at MRB and CHO. Prevailing VFR conditions Mon/Tue with any restrictions likely confined to diurnal t-storms. Light SE`ly winds Mon become SW`ly Mon eve and eventually N of W by Tue. && .MARINE... High pressure will remain in control of the weather through the weekend, with E`ly winds Fri and SE`ly Sat and Sun. While there could be some localized or brief enhancements, SCAs are unlikely at this time. Winds likely become S`ly Mon and possibly into Tue depending on the timing of the next front. Channeling could enhance winds along the bay Mon night. Could have SMWs for any stronger storms each afternoon/eve. && .TIDES/COASTAL FLOODING... Water levels should reach a minimum today in N`ly flow before snapping back tonight. Anomalies will rebound within onshore flow this weekend, with more sensitive locations potentially reaching Action Stage. Annapolis could approach minor flood thresholds by Sat night. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...None. MD...None. VA...None. WV...None. MARINE...None. && $$ DISCUSSION...DHOF/CPB AVIATION...DHOF/CPB MARINE...DHOF/CPB