Intense thunderstorms with heavy rains dampened bushfires on Australia's east coast on Friday to the relief of exhausted firefighters and farmers battling years of drought. The bushfires that have raged since September have killed 29 people and millions of animals, destroyed more than 2,500 homes and razed an area roughly a third the size of Germany. Victoria, New South Wales and Queensland, three of the states most affected by drought and bushfires, welcomed the drenching rain which fire services said would not extinguish all the blazes but would aid greatly containment. "Our fingers are crossed that this continues over the coming days," the New South Wales fire services said on Twitter on Friday. Severe storms are forecast to continue in many fire-stricken regions of New South Wales and Queensland, including areas that have not seen heavy rainfall for years, the Bureau of Meteorology in NSW said. "The recent rain has just been absolutely fantastic," said cattle farmer Sam White near the town of Guyra in northern NSW. "It's producing significant amounts of runoff, which is what we need, and it's getting into our dams." But the wet weather also comes with dangers, such as flash flooding and falling trees, many weakened by the intense bushfires. One wildlife park had to rescue koalas from floodwaters and beat back crocodiles with brooms. The heavy downpours have helped to clear the smoke-filled air, but Sydney, Canberra and Melbourne remained in the world's top 100 polluted cities, according to AirVisual's pollution ranking for major global cities. Melbourne, blanketed in thick smoke earlier in the week that disrupted the Australian Open qualifying matches and other sporting competitions, is forecast to again be shrouded by unhealthy air over the weekend when the tennis tournament begins. The smoke haze that has plagued Australia's major cities for weeks has been tracked by Nasa circumnavigating the globe. The US space agency's satellites showed on Thursday that there is also a large concentration of lower smoke over the Pacific Ocean. Of the 82 fires burning across New South Wales early on Friday, 30 were uncontained, according to fire authorities. An emergency evacuation order was issued for parts of Victoria's north-east with an out-of-control bushfire threatening the Buffalo River Valley. Australia will have to wait until March for rains heavy enough to bring sustained relief from dry weather that has fuelled deadly bushfires, the country's weather bureau said on Thursday. Australia's peak tourism body estimated the country's bushfire crisis has so far cost the industry almost A$1 billion ($690 million).