A record-breaking heatwave, described as a heat dome, swept across southeastern Australia, pushing temperatures toward 50°C in four states and triggering bushfires and smoke across the region.

Victoria and New South Wales logged some of their hottest temperatures on record around January 23–24, with Victoria hitting 48.9°C in Hopetoun and Walpeup and NSW recording near-record highs in multiple locations.

Victoria recorded its hottest day on Tuesday at 48.9°C, with Melbourne reaching around 45°C, while several NSW and SA towns also neared 50°C amid the heat.

Residents described the situation as terrifying and exhausting, but noted a strong sense of community and mutual aid during the crisis.

Climate change is identified as a contributing factor, supplying more atmospheric energy that helps extreme heat events persist and last longer.

Forecasts indicated a gradual easing of severe conditions by the weekend, though the risk of additional heatwaves remains through February and March.

Farm and utility infrastructure suffered significant damage, including loss of potable water due to fire and widespread power outages affecting over 100,000 homes.

The heat dome is a large high-pressure system that traps hot air aloft, suppresses cloud formation and rainfall, and blocks other weather systems, leading to persistent extreme heat with little relief.

Public health officials warned of heat dangers and urged hydration, highlighting heat as a leading weather-related risk linked to climate change.

Scientists warned that climate change increases the frequency and intensity of heatwaves, contributing to higher heat-related mortality.

Communities adapted by keeping refuges open and coordinating neighborly support and evacuation efforts to cope with the heat and fires.

Meteorologists attributed the prolonged heat to a blocking pattern that kept heat over southeastern Australia without a strong cold front to clear it.