Clusters of severe thunderstorms are expected to strike Australia’s southern regions over Thursday and Friday. The Bureau of Meteorology has issued severe weather warnings and forecasts related to these unusually widespread stormy conditions as they move through South Australia today and into Victoria. As of October 17th, there’s a risk of severe thunderstorms for parts of central and southern Australia. Some areas have already experienced golf ball-sized hail and intense winds. While we might not always think of thunderstorms as a threat, severe storms can be surprisingly damaging. The enormous Sydney thunderstorm of 1999 dropped an estimated 500,000 tonnes of…