🌊 US Weather Warriors MarineCast — Saturday, July 4, 2026
Holiday boating on tap with light winds early, but SW breezes build tonight with a chance of evening thunderstorms offshore.
Today on the Water: No active marine advisories, but extreme heat warnings and heat advisories cover much of Delmarva through 8 PM — hydrate hard and watch for heat stress on deck. Winds stay manageable through daylight before ramping up after sunset. Scattered showers and thunderstorms possible late in the day, mainly offshore.
Atlantic Coastal Waters (Lewes → southern VA coast): SW winds increase tonight to 10–15 kt with gusts to 20 kt, easing to S 5–10 kt after midnight. Seas building to 2–4 ft overnight with a short-period S swell around 2 ft at 4 seconds and a background SE 1 ft at 9 seconds. Chance of showers and thunderstorms in the evening.
Delaware Bay: Light and manageable today. Look for S winds around 5 kt this morning, becoming SE 10–15 kt with gusts to 20 kt this afternoon. Seas 1 ft or less early, building to around 2 ft by afternoon. Chance of afternoon showers and thunderstorms.
Chesapeake Bay & Delmarva-facing Waters: SW winds 5–10 kt early, backing SE 10–15 kt with gusts to 20 kt this afternoon. Waves 1–2 ft with SE 2 ft at 4 seconds over background SE 1 ft at 9 seconds. LWX notes weak synoptic gradients, so any Small Craft-level surges up the Bay are low confidence.
Wind & Seas Outlook: Peak winds and highest seas tonight offshore (SW gusts to 20 kt, seas 2–4 ft). Conditions ease sharply by Wednesday with the lightest winds and calmest seas of the stretch.
Marine Alerts:
- No active marine alerts.
- Land-based: Extreme Heat Warning and Heat Advisory in effect across much of Delmarva until 8 PM EDT — relevant for anyone launching or working the docks.
Radar Check: KLWX and KAKQ quiescent; KDOX last scan 08:47Z shows no cells within 50 nm. No lightning risk on radar right now, but afternoon convection is possible per the forecast.
Best Window to be Out: This morning through early afternoon — light winds, workable seas, minimal storm risk. Be off the water before evening thunderstorms fire.
Worst Window: Tonight offshore, with SW gusts to 20 kt, 2–4 ft seas, and thunderstorm chances.
Bottom Line: Good Fourth of July morning on the water if you launch early, get your run in, and beat the afternoon heat and evening storms back to the dock.
— US Weather Warriors #DelmarvaWeather #MarineWeather #BoatingWeather