Biography Wikipedia
Wikipedia:
Southerly is the name of a storm or front of air coming from the south. In the Southern Hemisphere these can be cold and have bad weather. In Wellington, New Zealand these storms are normally short and frequently have winds gusting between 120 km/h and 160 km/h though higher speeds are known. In Sydney, New South Wales, Australia these events are known as southerly busters.
In the hot Sydney summer, the land heats up rapidly each morning, and faster than the sea. The prevailing wind is a light south west offshore breeze that blows from land to sea, but by mid to late afternoon, the land rapidly cools and a north east convection current wind sweeps in from sea to land. This is a typical "sea breeze", but often it is strong offsea gale bringing a rapid fall in temperature, and a short, violent rain/hail storm.
A more persistent but potentially violent Sydney NE storm is known as a "black nor'easter" . This is not a convection wind, but a storm system that develops offshore which can last several days. This is heralded by the rapid build-up of dense black cloud that can convert to a gale in well under one hour.
Occasionally, when there is a strong colder system to the south west, the temperature is dramatically broken by an equally violent storm-laden south west wind, and it is this that is known as a "southerly buster".
