🌊 US Weather Warriors MarineCast — Friday, September 18, 2026
Light north winds and manageable water today, but a strengthening northeast pattern will turn hazardous later in the forecast.
Today on the Water: North winds remain below Small Craft Advisory levels today, with the calmest conditions on Delaware Bay and Chesapeake Bay. Radar shows a strong cell 44 miles southeast of Chincoteague moving northwest at 16 kt. It is heading toward the coast; boaters off the southern Virginia coast should watch for lightning and a quick hit of rain.
Atlantic Coastal Waters (Lewes → southern VA coast): West winds 5 to 10 kt become northeast late, with seas 2 to 3 ft. A south swell of 2 ft at 4 seconds mixes with an east swell of 2 ft at 8 seconds. The better ocean window is earlier today before the late wind shift. The radar cell southeast of Chincoteague is the near-term weather concern.
Delaware Bay: North winds run 5 to 10 kt with seas 1 foot or less and a west wave around 1 ft at 4 seconds. This is the steadiest option for smaller boats today, though showers remain in the broader forecast.
Chesapeake Bay & Delmarva-facing Waters: North winds hold at 5 to 10 kt with waves around 1 ft today. Conditions are workable on the Bay, but showers or thunderstorms may develop at times; the active cell south of Chincoteague is moving northwest toward land.
Wind & Seas Outlook: Waves build on Saturday, with northeast winds 15 kt and gusts up to 20 kt on Chesapeake Bay waters, producing 3 to 4 ft waves, occasionally 5 ft. The main deterioration comes Tuesday night: northeast winds reach 25 to 30 kt, with gusts up to 40 kt offshore and seas 7 to 9 ft, occasionally 13 ft.
Marine Alerts: No active marine alerts.
Best Window to be Out: Today during daylight hours, with Delaware Bay offering the lowest seas and light north winds.
Worst Window: Tuesday night, when strong northeast winds, large seas, and likely showers make offshore waters dangerous.
Bottom Line: Launches are reasonable today in protected waters, but southern coastal boaters need to give the northwest-moving Chincoteague-area cell and its lightning potential a wide berth.
— US Weather Warriors #DelmarvaWeather #MarineWeather #BoatingWeather