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Six-day Forecast of the Potential for High Sea Level In and Around Pago Pago Harbor, Tutuila, American Samoa

Caution: The forecast below is experimental and no promise of accuracy is implied; especially, the forecast is explicitly not accurate when either a tsunami, tropical storm or hurricane warning is in effect. In these latter cases, see either tsunamis or tropical storms/hurricanes.

SLpred graphic for Pago Pago Harbor, Tutuila, American Samoa


Red Line at Top

Indicates the sea level height that is exceeded by two percent of the observed daily Higher High Waters (HHW description) based on a 19-year historical record (excluding tsunamis).

Vertical Yellow Line

Time this forecast was created.

Dark Blue Curve

Observed Sea Level at Pago Pago Hbr. for previous 3 days. The measurement is relative to MLLW (Mean Low Low Water), a well-defined reference level (NOAA datum description)

Cyan Curve

Forecast Sea Level at Pago Pago Hbr. for next 6 days. The forecast is relative to MLLW, and includes tides plus multi-day sea level variations. The forecast is updated every four hours.

Additional Information

Click here for additional information about both the plotted variables and forecast accuracy.

Click here for the detailed technical report explaining the methods for producing the PacIOOS High Sea Level Forecasts.

The Six-day High Sea Level Forecast Tool was developed by M. Guiles, D. Luther and M. Merrifield,
and is maintained by M. Guiles.

Please consider acknowledging PacIOOS in any distribution or publication of data as follows: Data provided by PacIOOS (www.pacioos.org), which is a part of the U.S. Integrated Ocean Observing System (IOOS®), funded in part by National Oceanic and Atmospheric Administration (NOAA) Award #NA11NOS0120039.