- Water Quality
- Coastal Hazards
- Ocean Conditions
- Marine Ecosystems
- Data Management
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.
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 Hilo Hbr. for previous 3 days. The measurement is relative to MLLW (Mean Low Low Water), a well-defined reference level (NOAA datum description)
Forecast Sea Level at Hilo 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.
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.