A practical starting point
How to use Tide99
US NOAA tide predictions, observed water levels and station-level marine conditions, each with its own timestamp.
Search Tide99
Step 1
Start with a precise record
Use the name, identifier or place you want to investigate. The website scope is: US NOAA tide predictions, observed water levels and station-level marine conditions, each with its own timestamp.
Step 2
Compare like with like
Open the relevant records and guides below. Keep identifiers, geography, units and source dates together; a record with a similar name or a different reporting period may answer a different question.
Step 3
Take the evidence to the original source
Follow the source references before making a consequential decision. Treat missing or historical information as a limitation, and use the relevant authority or provider for a current determination.