This is a non-operational test website that will no longer be updated. For official OPC information and forecasts, please refer to the operational OPC website: https://ocean.weather.gov.
GWES Probabilistic Wave Height Guidance
Use the drop down menus below to change the display.
Notes on images above:
- The likelihood of exceedance is shown as a probability of 0 to 100 of waves heights (significant wave height) reaching or being greater than the chosen value.
- The 90th percentile represents the wave height value that 90% of the ensemble members are either less than or equal to (i.e., 18 feet).
- The 10th percentile is the wave height value that is represented by 10% of the contributing ensemble members.
- The mean is defined as the 50th percentile, that is, the wave height value represented reflects half the distribution is above and half is below this value.
- The maximum value is the highest value produced by any of the 21 ensemble members. It reflects the most severe conditions predicted by the ensemble prediction system.
The data are produced from the Global Ensemble Forecast System (GEFS) which is run every 6 hours and are created with 20 ensemble members.
Additional information for interpreting this data
More information is available from NOAA's Environmental Modeling Center (EMC).