A coastal flood warning covers Washington’s San Juan County from 6 a.m. to noon Pacific time Friday, Nov. 13. High tides and storm surge could push water 2.5 to 3 feet above ground level along low-lying shorelines, the National Weather Service in Seattle said Thursday.

Forecasters expect road closures and warn that water could reach homes, businesses and some infrastructure near the shore. The warning applies to the San Juan County forecast zone, which includes Friday Harbor, Eastsound and Roche Harbor, according to the regional forecast archived by the University of Washington. The National Weather Service advises residents to protect flood-prone property before the tide rises and to stay behind road barricades. Drivers should turn around if they cannot tell how deep the water is.

Where the advisory applies

A separate coastal flood advisory runs during the same hours for Seattle, Island County and other low-lying areas around Puget Sound, the Hood Canal and north to western Whatcom County. The weather service expects minor flooding in those areas, with 2 to 2.5 feet of water possible above ground level along exposed shorelines. Parking lots, parks and roads near the water could flood.

People heading to the islands Friday morning can check Washington State Ferries’ service alerts before leaving for the terminal. NOAA posts tide predictions and observed water levels at its Friday Harbor gauge. The county also offers local emergency alerts by text and email.