🌊 US Weather Warriors MarineCast — Tuesday, August 18, 2026
Light winds and modest seas dominate today, but patchy early fog and isolated afternoon showers and thunderstorms require attention.
Today on the Water: No active marine alerts. Coastal winds run around 5 kt, with seas near 2 ft offshore and 1 foot or less in Delaware Bay. Radar is quiet within 50 nm of Delmarva, but isolated showers and thunderstorms remain in the afternoon forecast. Patchy fog is possible early this morning.
Atlantic Coastal Waters (Lewes → southern VA coast): NW winds around 5 kt become NE late, with seas around 2 ft. Patchy fog early may restrict visibility. Tonight offers the smoother stretch: E winds 5 kt shift S late, then W after midnight, with SE waves 2 ft at 9 seconds. Isolated afternoon showers and thunderstorms are the weather concern.
Delaware Bay: N winds around 5 kt today, with seas 1 foot or less. Watch for patchy fog early and isolated showers and thunderstorms this afternoon. Tonight, SW winds around 5 kt become NW around 5 kt after midnight; seas remain 1 foot or less.
Chesapeake Bay & Delmarva-facing Waters: Light winds continue through the end of the week, shifting north to northwest today before returning southerly by late Wednesday. The best Bay conditions are Wednesday Night: SW winds 5 kt and flat waves. A few wind enhancements are possible along the Bay.
Wind & Seas Outlook: The next notable offshore sea build is Saturday, when SE winds reach 5 to 10 kt and Atlantic seas build to 3 to 5 ft with showers likely. Chesapeake winds increase Thursday afternoon into Thursday Night, reaching SE 10 to 15 kt before easing after midnight.
Marine Alerts: No active marine alerts.
Best Window to be Out: Tonight on Delaware Bay or the Atlantic coastal waters, after the afternoon shower and thunderstorm window, with 5 kt winds and seas of 2 ft or less.
Worst Window: This afternoon, especially where isolated thunderstorms develop and early fog lingers.
Bottom Line: Launchable for experienced boaters in light wind and low seas, but plan around reduced early visibility and get off the water if thunderstorms develop.
— US Weather Warriors #DelmarvaWeather #MarineWeather #BoatingWeather