High Tide Flooding Outlook for August 2025

Galveston Bay, Texas, and the Hawaiian Islands don’t normally have much in common, but this month they are the only U.S. locations where high tide flooding is possible, as the rest of the country’s harbors are predicted to have another mild month with no such high-water events in NOAA’s forecast. Note that while NOAA only makes these flooding predictions for harbors with National Ocean Service water level stations, other locations along the coast may experience similar high-water events during these time periods. In addition, real-time weather conditions, including wind direction and storm surge, may also increase the potential for flooding. In all locations, higher than normal high tides (and lower low tides) should be expected on or around the full moon, on August 9, and the new moon, on August 23 (in West Coast harbors, the new moon will be on August 22).

August 9 – Full Moon
August 23 – New Moon

Note that while NOAA only makes these flooding predictions for harbors with National Ocean Service water level stations, other locations along the coast may experience similar high-water events during these time periods. Real-time weather conditions, including wind direction and storm surge, may also increase the potential for flooding.

Make sure to print out the monthly tide chart from USHarbors so that you can stay on top of any potential flooding events in your favorite harbor.

Northeast: Possible & Likely Flood Days

• Coastal flooding based primarily on tides is unlikely this month.

Mid-Atlantic: Possible & Likely Flood Days

• Coastal flooding based primarily on tides is unlikely this month.

Southeast: Possible & Likely Flood Days

• Coastal flooding based primarily on tides is unlikely this month.

Gulf Coast: Possible & Likely Flood Days