Autumn will bring above-average heat and irregular rainfall to Santa Catarina.

The weather forecast for March, April, and May indicates above-average temperatures in Santa Catarina. Rainfall is expected to be near average in most of the state and near to below average in the west. Along the coast, March may see episodes of intense rainfall with high volumes. This information is based on the Epagri/Ciram forecast.

At the end of summer and the beginning of autumn, the risk of heavy rainfall events in a short period of time remains. Storms with lightning, hail, and strong winds continue to be frequent in the state. The agency recommends daily monitoring of weather warnings.

In March, the reduction in convective rainfall marks the transition between seasons. From the second half of the month, cold fronts advance more frequently through southern Brazil and concentrate most of the precipitation in Santa Catarina. The monthly average varies from 100 to 130 mm from the west to the plateau and from 150 to 210 mm on the coast. In April and May, the volumes decrease, with averages between 100 and 170 mm in the state.

Extratropical cyclones will become more frequent along the coast of Uruguay, Rio Grande do Sul, and Santa Catarina starting in March. These systems cause strong winds, rough seas, high surf, and risks to navigation. For the fall of 2026, there are indications of a greater occurrence of these systems near southern Brazil.

Warm air masses predominate in March, with a sequence of hot days, including at night. At the end of the month and in April, early mornings register a drop in temperature and a chance of frost in the higher areas of the Southern Plateau. More intense cold air masses are expected to advance from May onwards.

In the Equatorial Pacific, January showed negative anomalies associated with a weak La Niña. In February, the pattern shifted towards neutrality. The trend indicates continued warming of the waters and neutral conditions at the end of summer and during autumn, with monitoring for possible evolution towards El Niño in the spring.