Damage to motor vehicles from hailstorms and larger hailstone looks set to increase under some climate scenarios, a report has found.
The University of New South Wales study Changes in Hail Damage Potential in Major Australian Cities With Global Warming has investigated hailstorm probability under current and future climate changes across Australia’s main cities and regional areas.
It investigated an area covering 65 per cent of the Australian population, to estimate hail frequency and hailstone size along with accompanying winds, both now and under a scenario with a 2.4C increase in mean global temperature by 2100.
The team of academics recorded projections that show increases in hail frequency in the Sydney/Canberra and Brisbane regions and increases in maximum hail size around Melbourne, Sydney/Canberra, Kalgoorlie, and Perth.
The likelihood of large (10cm) hailstones hitting Melbourne would increase from once every 20 years to once every three years, according to results.
In Sydney the risk of this giant hail is calculated to be about once every three years but this would increase to every two years under the warming scenario.
Hard to forecast
Hail remains difficult to predict for forecasters who rely on radar for warnings of its imminence but identifying hail from other precipitation and in particular its size is problematic for forecasters.
In 2024 the Bureau of Meteorology partnered with major insurer Suncorp aiming for better forecasting that may allow for better damage prevention, particularly to vehicle body damage.
High Cost
2023 insurance claims from extreme weather cost the nation $1.6 billion in losses including about $170 million in motor losses from a single adverse event in Queensland around Christmas 2023.
The NRMA Wild Weather Tracker also found in the storms that hit Queensland and NSW this year, almost a quarter of Queenslanders experienced damage to their house or car during the floods and extreme weather.
Summer storms most often bring severe hailstorms damaging vehicles and autumn is traditionally the mildest season but the report details 1,387 severe weather motor claims during autumn 2025.
The NRMA report also predicts storms with large to giant hail are already becoming more frequent in the south and east of Australia with a predicted southerly shift in the areas at risk of hail in a warmer climate.