Forecast Myths

Forecast Period vs Wave Buoy Period

We get regular emails telling is that the forecast swell period is wrong. ThisĀ assessmentĀ is based, quite reasonably, on the regular differences between the model forecast and the numbers observed on a local wave buoy. However this difference doesn’t mean either is wrong. The explanation is that most wave buoys look at ‘average period’ of all swells where, more usefully, your forecast looks at peak period of each separate swell. The crucial thing to understand about model forecasting is we’re trying to simplify things in order to predict them. Most surfers know that swell height is the peak to trough size of the wave and that wave period is the time […]

Myth: Wave Buoy Forecasts

One of the most intriguing and for us, frustrating, myths in surf forecasting is that your local forecast comes from a wave buoy. It leads to a range of misconceptions, that your forecast is less accurate because your beach is ‘further away’ from the nearest wave buoy, or just that surf forecasts aren’t very accurate because the buoys “aren’t very accurate”. This myth persists a decade after we first started running the MSW website perhaps strengthened by some sites which talk about ‘virtual buoys’ when they simply mean swell forecasts. A wave buoy sits in the Ocean and bobs up and down with the waves, it records this motion and […]