Severe Weather Warnings
The Bureau of Meteorology issues Severe Weather Warnings whenever severe weather is occurring in an area or is expected to develop or move into an area. The warnings describe the area under threat and the expected hazards. Warnings are issued with varying lead-times, depending on the weather situation, and range from just an hour or two up to about 24 hours. They are issued for:
- Sustained winds of gale force (63 km/h) or more
- Wind gusts of 90 km/h or more
- Very heavy rain that may lead to flash flooding
- Abnormally high tides (or storm tides) expected to exceed highest astronomical tide
- Unusually large surf waves expected to cause dangerous conditions on the coast
- Widespread blizzards in Alpine areas
Severe Thunderstorm Warnings
The Bureau of Meteorology issues Severe Thunderstorm Warnings to alert communities of the threat of more dangerous thunderstorms.
A severe thunderstorm is one that produces any of the following:
- Large hail (2cm in diameter or larger)
- Damaging wind gusts (generally wind gusts exceeding 90 km/h)
- Heavy rainfall which may cause flash flooding
- Tornadoes