Australia is entering its severe weather season, which runs from October through April, with forecasts indicating a potentially intense period marked by record-level heat, increased storm activity, and heightened bushfire risk. Experts cite the interplay of climate drivers, including a rapidly intensifying El Niño event and elevated ocean temperatures in both the Indian and Pacific Oceans, as key factors shaping this outlook.
El Niño, a Pacific climate phenomenon known for typically suppressing rainfall, is approaching some of the strongest levels ever recorded. However, unusually warm seas surrounding much of the Australian coastline may counteract El Niño’s usual drying effect, resulting in a complex and variable rainfall pattern across the country.
Temperature forecasts point to one of the hottest severe weather seasons on record, with about a 25% chance that it will become the hottest. Heatwaves are expected to be more frequent and intense through summer, driven by warm ocean waters that reduce overnight cooling. This lack of nightly temperature relief is likely to increase stress on public health and power infrastructure nationwide.
In addition to heat, the season is expected to bring an elevated risk of severe thunderstorms, particularly in the latter part of 2026. A warmer atmosphere can hold greater moisture content, making storms potentially more intense and hazardous. Areas of New South Wales (NSW) and central Australia may face higher incidences of damaging winds, large hail, heavy rainfall, and flash flooding. Severe thunderstorms already represent the largest share of weather-related insurance claims in Australia, and this season could see a surge above normal levels.
Rainfall patterns are projected to be uneven. Western and central Australia are favored to experience wetter-than-average conditions for the remainder of 2026, while parts of the southeast, including some areas of NSW, may see below-normal precipitation. The far north is expected to remain drier than usual into early 2027, though forecasts for other regions hold significant uncertainty.
NSW, in particular, could see some of the most volatile weather this season. Hotter continental temperatures combined with warm coastal waters are likely to fuel more frequent and severe thunderstorms characterized by heavy rainfall, strong winds, and large hailstones. Inland areas of the state are expected to receive above-average rainfall during the coming months, but outlooks for early 2027 indicate an equal chance of wetter or drier conditions.
Overall, the combination of record heat, unstable atmospheric conditions, and variable rainfall highlights the need for heightened readiness for a severe weather season that may challenge Australia’s climate records and emergency response capacities.