A cold front is bringing the possibility of snowfall to the mountainous regions of Rio Grande do Sul and Santa Catarina [1].
This weather pattern signals the onset of the colder season in southern Brazil, potentially disrupting regional travel and agricultural activities as temperatures plummet.
Meteorologists said that a polar air mass, combined with the movement of an extratropical cyclone, is driving the temperature drop [2]. The front was expected to reach the southern region on April 25, 2026 [1]. Following the initial arrival of the system, a more significant decrease in temperature was forecast to begin on April 27, 2026 [3].
Reports said that some areas in the south have already seen temperatures fall below 0°C [4]. While some weather services emphasized the risk of heavy rain and storms, other reports highlighted the likelihood of snow in the highlands [5, 6].
"The beginning of winter in Brazil will be marked by rains and the possibility of snow in the mountains of Rio Grande do Sul and Santa Catarina," a CNN Brasil report said [5].
The interaction between the polar air and the cyclone creates the specific atmospheric conditions necessary for frozen precipitation. A report from Terra said the advance of the polar air mass and the extratropical cyclone should drop temperatures in the South starting Sunday, April 25 [2].
Local authorities have monitored the risk of frost and severe weather. An Estadão report said a new polar air mass arriving with a cold front should cause a sharp drop in temperatures starting Monday, April 27 [3].
“The beginning of winter in Brazil will be marked by rains and the possibility of snow”
The convergence of a polar air mass and an extratropical cyclone creates a volatile weather window in southern Brazil. While snowfall is a rare and visually striking event in the serras, the accompanying sub-zero temperatures and potential for frost pose a direct threat to local crop yields and infrastructure. The discrepancy in forecasts between rain and snow underscores the instability of the front as it interacts with the region's high-altitude geography.
