Australia has a diverse range of climate zones, varying from tropical regions in the north through the expanses of the interior's arid to semi-arid to temperate regions in the south and east, to tropical in north. Temperatures fluctuate from above 50 degrees Celsius to well below zero.
Much of Australia is fairly arid, 80% of it having a rainfall of less than 600 millimetres per year, while 50% has even less than 300 millimetres. Australia's rainfall is easily the lowest of the five continents (excluding Antarctica). The uniqueness of Australia's flora and fauna is partly due to these features of our climate.
Cyclones have destructive winds, torrential rains, storm surges, and wild seas which have inflicted a heavy toll on communities and travellers in their paths, causing them to be the most feared of the weather phenomena to affect Australia. As they move into higher latitudes or track inland, they lose contact with the warm tropical oceans necessary to sustain them, and weaken. A weakening cyclone can continue to cause flooding for inland communities.
Cyclones have caused an insurmountable amount of damage and deaths over the years, and will always have the potential to take lives. However, heavy death tolls are less likely in Australia now due to the watchful eye of satellites, and enhanced warning and communication capabilities.
You will find that most Australians can vividly recall at least one major thunder, wind or hailstorm in their area. They come in all manor and form, and all over Australia. Tornados have demolished towns and crops. Dry lightening storms, though absolutely spectacular to view, have caused major bushfires. Hail storms have covered farms and cities in a blacket of white with widespread destruction. Dust storms can strip paint off your houses and vehicles, mess with electrical appliances and contaminate water supplies. According to Emergency Management Australia, severe thunderstorms cause more damage in Australia each year than any other natural hazard, and the damage bill in individual cases has gone into the hundreds of millions of dollars.
Drought has always been a part of living in Australia, particularly in areas away from the wetter coasts and ranges. Droughts are probably the most economically costly climatic phenomena that afflict Australia. Droguhts can cause fires, dust-storms, general land degradation, crop failure and stock losses. The most damaging type of drought is when one or two very dry years follow several years of below-average rainfall. It is because of the strong occurance of drought, or drought like conditions that nearly all of Australia has water restrictions.
Most of the country is susceptable to flooding, either in the form of localized flash flooding from intense thunderstorms, or more widespread and longer lasting inundations which result from heavy rain over the catchments of river systems. Lost, or stock losses can be in the tens of thousands, and damage to homes, businesses, roads, etc can run into hundreds of millions of dollars. Apart from being the costliest form of natural disaster in Australia,floods have some beneficial aspects, such as cleansing excess salt from the soil and recharging underground aquifers.
Hot weather, long dry periods, and volatile natural vegetation makes most parts of Australia particularly vulnerable to fire. South eastern Australia has the reputation of being one of the three most fire-prone areas in the world. Fires has always claimed many lives throughout history, it has destroyed people's homes and livelihoods, and reduced thousands of hectares of forest to charcoal and ash. Fires are able to sweep even the most arid regions in years when good wet season rains are followed by a long dry spell. The dry summer months are the danger time for southern Australia, as are the winter months over northern Australia.
Australia can be subject to fierce heat, with very high temperatures (high 30s or even 40s) can persist for days, which can lead to heat exhaustion or death, particularly among the very young or old. It accounts for a higher death toll in Australia than any other natural hazard. By November, the average maximum temperatures over northern and central Australia have already climbed into the high 30s and low 40s in parts. The heat does not relent until the following autumn.
Outside the highland areas of south eastern Australia, snow is somewhat of a rare event. At higher elevations of south eastern Australia, snow can often persists for weeks or months at a time, but it can vary substantially from year to year. When it does persist, it produces some great skiing seasons! In some years, such as 1973 (when it was too warm) and 1982 (too little precipitation), the ski season fails. Snow-making equipment has taken this burden away from ski resort operators.