Brazil's winter season began Sunday, June 21, 2026, with an intense cold wave bringing temperatures to 0°C in the South and Southeast [1].
The timing and severity of this temperature drop are significant because they precede a forecasted El Niño event that could trigger volatile weather extremes. This combination of early deep freezes and subsequent warming may disrupt agricultural cycles and public infrastructure across the region.
Reports said that temperatures in the South and parts of the Southeast are expected to fall below 0°C [1]. A strong polar air mass is credited with driving these temperatures to around 0°C across much of the South region [3]. This mass has brought frost and freezing conditions to areas that typically experience more moderate winter transitions.
While the current freeze is the immediate concern, meteorologists are tracking a high-probability El Niño event. The probability of this event exceeds 90% [2]. Reports said this phenomenon threatens Brazil with a cycle of drought, extreme heat, and flooding [2].
There is some disagreement among weather sources regarding the immediate influence of El Niño. Some reports said the phenomenon will not cause significant changes to the climate during June [3]. Other sources link the current intense cold to the upcoming El Niño, suggesting the event will later produce severe heat waves [1].
The polar air mass continues to spread across the country, maintaining the cold grip on the southern states as the winter solstice marks the official start of the season [1], [3].
“Winter started on 21 June 2026”
The intersection of a strong polar air mass and a high-probability El Niño creates a volatile climatic outlook for Brazil. While the immediate risk is frost and freezing temperatures in the South, the long-term concern is the transition to extreme heat and drought. This instability often leads to increased pressure on the national power grid and can threaten crop yields in Brazil's primary agricultural hubs.
