Rare Stratospheric Warming Threatens Australia's Weather

As of September 26th, 2025, a rare and unusual rise in stratospheric temperatures over Antarctica has climate experts closely monitoring its potential impact on weather patterns in the coming months. The phenomenon, known as sudden stratospheric warming, is only the third such event recorded in the southern hemisphere, with previous occurrences in 2002 and 2019.

The current warming has seen air temperatures 30 kilometers above the Southern Ocean and Antarctica climb to around -20°C, a significant increase from the typical -50°C. This dramatic shift is accompanied by a slowdown in the powerful winds of the polar vortex, which normally reach speeds of 200 km/h but are now down to 100 km/h.

These changes in the stratosphere are likely to drive warmer and drier weather at the surface, particularly in southeast Australia. However, the full effects remain partly unknown, as the Bureau of Meteorology has forecast wetter conditions, potentially creating a "balancing act" between the stratospheric and oceanic influences.

One positive outcome of the stratospheric warming is a reduction in the size of the ozone hole above Antarctica. As temperatures rise above the threshold for ozone destruction, the hole is expected to shrink, providing some relief.