Wave forecasts – now more detailed and reliable
25 November 2013
Meteorologists at the Bureau are now applying improvements to computer models used for wave forecasting. Typically, computer model predictions differ from wave height observations by half a metre around Australia. During high wave events or when wave fronts are difficult to predict, this difference can extend to a metre or more. Our new technique further improves these wave forecasts.
Higher resolution forecasts
The Bureau's new approach provides the highest resolution wave forecasts for Australia's coastline, using a 6-kilometre grid spacing rather than the usual 40-kilometres. This resolution highlights local scale features that other wave models miss, such as bays protected from the prevailing swell and refraction around geographic features and islands. This is shown clearly in the comparison below.
Left: Wave forecast for Perth area from a computer model. Wave heights are unaffected by Rottnest Island. Right: Wave forecast for Perth area created by our meteorologists. Note the lower wave heights caused by Rottnest Island.
More accurate wave forecasting can have a dramatic effect on marine activities. For instance, the wave height for the Fremantle Port and harbour entrance produced by computer models (shown on the left panel above) was over 1.5 metres. With our improvements, the wave height forecast was only 0.5 metres, saving the Harbour Master from unnecessarily restricting port activities.
More reliable forecasts
Wave forecasts for the next day are correctly predicted to within one metre on nine out of ten occasions. During a recent large wave event in Tasmania, our meteorologists correctly forecast a 10-metre wave height within half a metre, four days ahead of the event. In contrast, two other computer models predicted 8.5 and 12-metre waves.
Use our wave forecasts
Waves are one of the five vital checks before going boating, and surfers can also make use of our wave forecasts. See either: