Scorching Heatwave Ushers in Summer for Southern Brazil’s Santa Catarina State
Table of Contents
A heatwave is gripping the Brazilian state of Santa Catarina (SC) as the Southern Hemisphere officially welcomes summer on December 21, 2025, at 12:03 pm. Residents are bracing for a weekend of hot and muggy conditions, with temperatures expected to soar above 30°C (86°F) and persistent, stifling humidity.
Weekend Forecast: Sun, Clouds, and Isolated Storms
Saturday, December 20th, will see a mix of sun and some clouds across SC. Though, localized rainfall is anticipated, particularly during the night in Greater florianópolis and the northern regions of the state, driven by maritime circulation. Winds will be moderate, originating from the northeast, with gusts reaching 40 to 50 km/h (25 to 31 mph) along the Litoral Sul.
Sunday, December 21st – the first official day of summer – promises continued heat and sunshine, but with increased instability. Isolated thunderstorms are likely to develop in the afternoon, especially in the Far-West, West, and Midwest areas of SC. Similar to Saturday, Greater Florianópolis and northern SC can expect intermittent rain, particularly at the beginning and end of the day, due to ongoing maritime influences. Winds will shift from northeast to northwest, remaining moderate with gusts between 40 and 60 km/h (25 to 37 mph) along the Litoral Sul.
Early Week outlook: Lingering Heat and Approaching Cold Front
The heat will persist into Monday and Tuesday,December 22nd and 23rd,with variable cloudiness and sunny openings throughout SC. isolated rain showers are expected in the afternoons and early evenings, particularly in the West and Midwest, as instability from Rio Grande do Sul (RS) and an approaching cold front begin to influence the region. The possibility of localized, intense storms cannot be ruled out. Temperatures will remain high, with continued stuffy air. Winds will be primarily from the northeast, shifting to the south on Tuesday, and remaining moderate with gusts.
Cooling Trend Expected on Christmas Eve
By Wednesday, December 24th, a change in the weather pattern is anticipated. skies will be partly cloudy to overcast across SC, with isolated showers throughout the day.Temperatures are expected to decrease slightly compared to previous days. Winds will shift to a southwest to south direction, remaining weak to moderate with gusts.
According to Marcelo Martins, a meteorologist with the Epagri/Ciram weather monitoring center, Santa catarina is utilizing a new system for weather forecasting and climate monitoring. This system doesn’t adhere to conventional IBGE political-administrative divisions, instead grouping areas based on shared rainfall and temperature patterns. This approach, Martins explains, allows for a more precise and effective method of weather forecasting and climate monitoring within Santa Catarina.
News Report Summary:
Why: A heatwave is impacting Santa Catarina, Brazil, coinciding with the start of summer. The state is experiencing high temperatures and humidity, with a forecast of isolated storms and an approaching cold front. A new weather monitoring system is being implemented.
Who: The heatwave is affecting residents of Santa Catarina (SC). Marcelo Martins, a meteorologist with epagri/Ciram, is involved in the implementation of the new weather monitoring system.
What: Santa Catarina is experiencing a heatwave with temperatures exceeding 30°C (86°F). The forecast includes a mix of sun, clouds, isolated thunderstorms, and an eventual cooling trend by Christmas Eve.A new weather monitoring system, based on climate
