A polar air mass has swept across Brazil, bringing a significant cold wave and rainfall to the Southeast region.

This weather pattern disrupts normal seasonal expectations and impacts agriculture and public health in the affected states. The movement of the air mass, combined with strong nocturnal radiative loss and a lingering cold front, has driven temperatures down across the South, Southeast, and Center-West.

According to forecasts from the meteorological service Climatempo, the cold wave reached its peak intensity on May 12, 2026 [1]. While initial projections indicated the system would begin to lose strength on the afternoon of May 13, 2026 [2], the cold persisted longer than expected.

Reports indicate that the effects of the polar air mass remained influential well into the following month. Record low temperatures continued to be registered in areas of the Southeast and Center-West as late as June 8, 2026 [3].

The Southeast region faced the dual challenge of plummeting temperatures and coinciding rain. This combination increased the risk of respiratory illnesses, and complicated transport in urban centers.

Meteorologists said that the persistence of cold mornings into early June suggests a more stable polar influence than originally forecast. The interaction between the cold front and the specific geography of the Center-West and Southeast regions amplified the temperature drop, leading to the record lows observed in June [3].

Local authorities have monitored the situation as the polar air mass moved over the country, tracking the impact on energy consumption and the stability of the power grid during peak heating periods.

“A polar air mass has swept across Brazil, bringing a significant cold wave and rainfall.”

The discrepancy between the initial May forecast and the record lows recorded in June suggests an unusually persistent polar air mass. This volatility indicates that traditional seasonal transitions in Brazil's Southeast and Center-West are becoming more unpredictable, potentially requiring updated infrastructure and public health responses to prolonged cold snaps.