This tool brings together real-time water levels, 48-hour forecasts of water levels, and historic flooding information into one online tool to help decision makers and coastal residents understand both short-term risks—such as an approaching hurricane or nor’easter—as well as longer-term risks, such as high-tide flooding and sea level rise. Boaters and fishermen can use the tool to get information on their latest local tides.  

The product features both a map-based view, where users can see which stations across the U.S. may be flooding, and a more detailed station view, where real-time water levels and historical data for a specific location are highlighted. Emergency managers and other coastal decision makers can use this information to understand and prepare for the impacts of coastal flooding; the coastal planning community can use this information to gain a better understanding of past peak water level events and the increased frequency of days when flooding is possible as sea levels change.

Most stations in Alaska and all Great Lakes stations are not yet available; however, CO-OPS is working with partner agencies on establishing relationships between measured water levels and flooding in order to provide the same level of information for all locations in the near future. By default, water levels are displayed relative to Mean Higher High Water (MHHW), the average highest tide in a day, but can be adjusted to other Tidal Datums as needed.

The ability to monitor water levels in the path of a tropical storm, hurricane, or nor’easter in real time is particularly important, given the potentially significant threats to life and property. NOAA’s popular Storm QuickLook information product will also be made available through this tool. The latest tropical cyclone track forecast and areas under active NWS coastal flood advisories and storm surge watches or warnings will automatically be displayed on top of the real-time flood information.