FNUS71 KLWX 221133 FWSLWX Spot Forecast for Chuck Brown Day Event...National Park Service National Weather Service Baltimore MD/Washington DC 733 AM EDT Sat Aug 22 2026 Forecast is based on forecast start time of 0800 EDT on August 22. If conditions become unrepresentative...contact the National Weather Service. Please contact our office if you have questions or concerns with this forecast. .DISCUSSION... While some very light showers or sprinkles are possible this morning, thunderstorms are not expected until the afternoon. Any additional rain this morning would be brief and insignificant. The best chance for seeing a heavier shower or thunderstorm will be during the afternoon, mainly between 3 PM and 7 PM and a second late night round of showers or thunderstorms around midnight tonight. An area of low pressure along the Mid-Atlantic coast will ride along a stalled boundary and bring rain and some thunderstorms throughout the day today. Additionally, a cold front will push through later this evening into tonight, bringing another chance for showers and storms. High pressure tracks in from the Tennessee and Ohio Valleys early next week which leads to a cool down with less humidity. Dry weather is now expected Sunday and through the first half of next week. .REST OF TODAY... Sky/weather.........Mostly cloudy (75-85 percent). Numerous showers and isolated thunderstorms early in the morning, then scattered showers and thunderstorms in the afternoon. Chance of pcpn......70 percent. Chance of thunder...30 percent. Max temperature.....Around 79. Min humidity........77 percent. Surface winds (mph).Light winds becoming east 5 to 7 mph in the late morning and afternoon. TIME (EDT) 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........81 79 85 83 80 72 77 80 73 83 Weather cov.....NUM NUM NUM SCT SCT ISO SCT SCT SCT SCT Weather type....RW RW RW RW RW RW RW RW RW RW Tstm cov........ ISO ISO ISO ISO ISO ISO SCT Chc of pcpn (%).70 70 60 30 30 20 40 40 30 50 Chc of thdr (%).10 10 10 20 20 20 20 20 20 30 Temp............69 71 73 74 73 75 77 77 78 79 RH..............100 100 93 90 93 87 82 85 82 77 Surface wnd dir.E E E E E E E E E E Surface wnd spd.3 3 5 6 6 6 7 7 7 7 Surface wnd gst.7 7 9 10 12 12 12 12 12 12 .TONIGHT... Sky/weather.........Mostly cloudy (65-75 percent). Showers likely and chance of thunderstorms in the evening, then chance of showers and slight chance of thunderstorms overnight. Chance of pcpn......60 percent. Chance of thunder...30 percent. Min temperature.....Around 68. Max humidity........100 percent. Surface winds (mph).East winds 5 to 6 mph early in the evening becoming light. TIME (EDT) 6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM Sky (%).........72 76 75 74 67 70 73 66 78 63 72 63 Weather cov.....CHC CHC CHC CHC LKY CHC CHC CHC CHC CHC SCH Weather type....RW RW RW RW RW RW RW RW RW RW RW Tstm cov........CHC CHC CHC CHC CHC SCH SCH SCH Chc of pcpn (%).50 40 40 50 60 40 40 30 30 30 20 10 Chc of thdr (%).30 30 30 30 30 20 20 20 10 10 10 10 Temp............77 76 74 73 72 71 71 70 70 70 69 69 RH..............85 87 90 93 97 100 100 100 100 100 100 100 Surface wnd dir.E E E E NE SE NW NW S SW SW SW Surface wnd spd.6 5 3 2 2 2 1 1 1 1 1 2 Surface wnd gst.10 9 8 6 5 5 3 3 3 3 5 6 .SUNDAY... Sky/weather.........Mostly sunny (25-35 percent). Chance of pcpn......10 percent. Chance of thunder...8 percent. Max temperature.....Around 84. Min humidity........53 percent. Surface winds (mph).Light winds becoming west 5 to 10 mph early in the morning. TIME (EDT) 6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM Sky (%).........56 49 33 7 9 4 7 10 21 49 46 47 Weather cov..... Weather type.... Tstm cov........ Chc of pcpn (%).10 10 0 0 0 0 0 0 0 0 0 0 Chc of thdr (%).10 10 0 0 0 0 0 0 0 0 0 0 Temp............68 68 70 72 76 79 80 81 82 83 84 83 RH..............100 100 100 93 82 69 67 60 56 55 53 53 Surface wnd dir.SW SW W W W W W W W W W W Surface wnd spd.2 3 5 6 8 9 10 10 10 10 10 9 Surface wnd gst.6 7 9 10 15 16 17 17 17 17 17 16 $$ Forecaster...Rosa Requested by...Ruhi Ellis Type of request...OTHER .TAG 2620231.0/LWX .DELDT 08/22/26 .FormatterVersion 2.0.0 .EMAIL ruhi_ellis@nps.gov