Tides: predictions, not for navigation
Tide times and heights on this site are NOAA’s astronomical predictions, not observations or forecasts. Wind, air pressure, river flow and storms can move the water a foot or more and shift the times. Do not use them for navigation; use official nautical charts and NOAA’s own products, and watch the water.
Lake levels: provisional, check the agency
Lake levels are provisional readings from Corps of Engineers and USGS gauges. They can be wrong, late, revised or missing. Before you launch a boat, swim, or travel to a lake, check the operating agency for closures, ramp status and flood releases. In a flood, follow the National Weather Service and local officials.
Water temperature
A sensor reads one spot, sometimes miles from the beach; a satellite reads the surface skin of the sea once a day. The water where you swim can be warmer or colder. Rip currents, not temperature, are the main danger on most beaches: swim near a lifeguard.
No warranty
The site is provided as is, without warranty of any kind. We are not responsible for decisions made on the strength of it.