The monthly tide predictions and lunar data for Guam are provided as a public service of the Marine Laboratory.  Data for the tide predictions are provided by the National Ocean Service, National Oceanic and Atmospheric Administration, U. S. Department of Commerce.  Users of these charts are cautioned to note that predicted tides are based on astronomical data and that local winds and barometric conditions may produce noticeable deviations from the predictions.  Generally, tides on the open coast occur a little earlier than shown here for Apra Harbor.  All times for tidal and lunar data are corrected for Time Meridian 150° E longitude.

| Marine Laboratory Home Page | University of Guam Home Page |