🌊 US Weather Warriors MarineCast — 2026-05-20
Small Craft Advisories are up on the mid and lower Chesapeake through 8 PM tonight, and conditions get worse offshore by Thursday night.
Today on the Water: SCAs cover the Chesapeake from North Beach down through Smith Point and into Tangier Sound until 8 PM EDT. Expect channeling winds on the Bay this afternoon and evening, with showers in the mix across all three zones. Offshore is the most manageable zone today, but the window closes fast as the week wears on.
Atlantic Coastal Waters (Lewes → southern VA coast): SW winds 10 to 15 kt today, backing S 15 to 20 kt late. Seas 3 to 4 ft on a 6-second S swell with a longer 9-second SE component underneath. The cleanest ride of the day is this morning before the southerly fills in.
Delaware Bay: Showers likely tonight with N winds easing to 5 to 10 kt and seas a foot or less. Conditions build Friday as E winds reach 15 to 20 kt with gusts to 25 kt and seas climb to 2 to 4 ft.
Chesapeake Bay & Delmarva-facing Waters: SCA in effect until 8 PM. SW 5 to 10 kt early shifts NE 15 to 20 kt with gusts to 25 kt this afternoon, waves building 3 to 4 ft, occasionally 5 ft. Showers likely. LWX notes Special Marine Warnings are possible this afternoon.
Wind & Seas Outlook: Peak winds arrive Thursday night offshore — NE 15 to 20 kt rising to 20 to 25 kt with gusts to 30 kt. That same window brings the highest seas: 5 to 6 ft, occasionally 9 ft.
Marine Alerts:
- Small Craft Advisory — Chesapeake Bay North Beach to Smith Point, Tidal Potomac to Smith Point VA, Patuxent to Broomes Island, Tangier Sound, Bloodsworth Island waters — until 8:00 PM EDT today.
Best Window to be Out: This morning offshore, before the southerly stiffens late and before Bay channeling kicks in this afternoon.
Worst Window: Thursday night offshore — gusts to 30 kt and seas to 9 ft.
Bottom Line: Bay boaters should stay tied up under the SCA; offshore crews can squeeze in an early run but be back before the wind shifts south.
— US Weather Warriors #DelmarvaWeather #MarineWeather #BoatingWeather