Hailstorm frequency has increased by 40% around Sydney and Perth since 1979

Increases in hail frequency over Sydney, Canberra and Perth were mostly driven by atmospheric instability, researchers say. Photograph: Rohan Thomson/Getty Images

The frequency of hailstorms has increased by about 40% around Sydney and Perth over the last four decades, while hail activity has decreased across much of the rest of the country, new research has found.

Scientists from the University of New South Wales and the Bureau of Meteorology analysed trends between 1979 and 2021, finding that hail-prone conditions had increased significantly over Australia’s south-east and south-west.