Fires across Australia's most populous state are now contained for the first time in nearly six months, authorities said on Friday, as heavy rains aid firefighters and boost some dam levels to their highest in nearly two years.

Australia has been battling hundreds of blazes since September in an unusually prolonged summer wildfire season that was fueled by three years of drought, which experts have attributed to climate change.

Aided by storms that lashed Australia's east coast earlier this week, the New South Wales Rural Fire Service said 24 blazes remain alight across state, though all are now under control.