Know what the forecast is telling you
Wind can change direction and strength very quickly. It is important to understand the key terms when reading a weather report.
- Wind speed over the water is given in knots. Wind mentioned in forecasts refers to the average wind over a 10 minute period at a height of 10 m.
- Gusts are increases in wind speed lasting for just a few seconds. They typically range 30-40 per cent greater than the average wind speed.
- Squalls are a sudden large increase in wind speed (usually accompanied by a change in wind direction) that lasts several minutes and then suddenly dies.
The Bureau of Meteorology issues a:
Strong wind warning
For winds averaging more than 25 knots and up to 33 knots
Gale warning
For winds averaging 34 knots and up to 47 knots
Storm warning
For winds averaging 48 knots or more
Maritime Safety Victoria strongly advises operators of small craft not to go boating when one of the above weather warnings has been issued.
The Bureau of Meteorology’s marine forecasts describe mean conditions over reasonably large areas such as Northern Bass Strait or Port Phillip. Reference to squalls and thunderstorms alert vessel operators to adverse weather conditions expected for short periods of time within the forecast period. Forecasts may not reflect local conditions where topographic influences might channel or block wind and affect wave development. Vessel operators should be familiar with local variations in certain wind streams before venturing out – ask the locals for advice.