We have just released an update years in the making to improve our surf height predictions based on comparing the Surf Captain wave model data to buoy data. This update will correct the wave model biases and provide a more accurate forecast for locations with a buoy nearby.
Wave model software is the most valuable tool available for predicting upcoming swell events and forecasting surf heights for the future. In contrast, buoys that measure waves are the best tool for understanding the current state of waves at specific locations. Buoys take real time measurements, whereas the wave model provides only an unvalidated prediction.
Surf Captain launched in August 2020, and since then, we have been comparing our wave model output with buoy data to validate our model prediction. This is being done at buoys along the United States, Canada, and Caribbean. In general the wave model does an incredible job of predicting the open ocean waves, mostly within a 5% error. We have found, however, there are some scenarios where the model has larger biases, up to 20%-30%+. These higher error scenarios tend to be with steep angled swells to the coastline, where the model fails to accurately represent the amount of wave energy at these swell frequencies. With the latest Surf Captain update, we are now correcting the surf heights based on our buoy validation when there is a buoy near the forecast location.
As an example, if the wave model is calling for a 2ft @ 17sec SSW swell for Huntington Beach, but at nearby buoy 46253, the model under predicts the wave heights at this swell frequency by an average of 15%, then we will increase the surf height forecast by 15%.
You can see the adjustment in the current forecast for Huntington Beach for Wednesday, March 26th.
Without the correction, the forecast is for 3-4β+ surf.
With the correction, the forecast is for 4-5β surf.
In this example, going from 3-4+ft to 4-5ft may not seem like a significant change, but the ability to identify and correct wave model biases is a significant update in helping improve the forecast accuracy.