Warmer conditions around the western Pacific have led to torrential rain and burst rivers

Dangerous and widespread flooding has been widely reported over the past week in eastern parts of Australia, particularly New South Wales. Tens of thousands of people have been forced from their homes after incessant torrential rain led to significant flooding from burst rivers.

The central Pacific Ocean is currently in a weakening “La Niña” state, whereby sea surface temperatures in the eastern Pacific are lower than normal, while in the western Pacific, particularly around Indonesia and eastern Australia, they are warmer than normal. This increased warmth in the latter raises moisture content and tends to lead to wetter conditions. This has been the driver for the huge volumes of rain witnessed over the past few days, generated by a series of Pacific storms.