As a cold front approaches São Paulo, residents are bracing for a significant drop in temperatures and intense rainfall starting Thursday, April 3, 2025. According to Climatempo, this weather change could bring a cold air mass that may result in a large thermal shock across the state.
The National Institute of Meteorology (Inmet) has issued an orange alert, indicating a risk of severe rain between the early hours of Friday, April 4, and the end of Saturday, April 5. Forecasts suggest rainfall amounts could reach between 30mm and 60mm per hour, or 50mm to 100mm per day, accompanied by strong winds with gusts ranging from 60km/h to 100km/h. This alert encompasses the Metropolitan Region of São Paulo as well as the Ribeira and Paraíba Valleys.
Climatempo warns that the risk of storms will be heightened on Thursday, due to the cold front's approach, which is expected to create conditions conducive to the formation of heavy clouds. The temperature is projected to begin its decline on Friday, as overcast skies, rain, and polar winds take hold.
In Santos, the Civil Defense anticipates rain beginning Thursday, which could intensify by the afternoon. By Friday and Saturday, precipitation could exceed 100mm, with wind gusts potentially surpassing 80km/h. As a precaution, Inmet has also maintained a yellow alert for intense rain until the morning of April 3, forecasting rain between 20mm and 30mm per hour.
The weather shift has already begun to impact daily life in São Paulo. On Thursday morning, parts of the city woke up to rain, a precursor to the heavier downpours expected later in the day. The Civil Defense has activated a crisis cabinet to ensure a rapid response to any potential damage caused by the storms.
In the capital, the rainfall forecast for Thursday and Friday could total 90mm, exceeding the historical average for April, which is 87mm. The coastal region, particularly in Ubatuba, is expected to bear the brunt of the rainfall, with forecasts suggesting up to 350mm.
As the rain continues, the Civil Defense has issued warnings about the risks of flooding and landslides, especially in vulnerable areas. Residents are advised to be vigilant, particularly if they notice signs of structural instability in their homes, such as cracks in walls or unusual water flow.
In terms of temperature, the cold front is expected to significantly cool down the region. By Saturday, April 5, temperatures in São Paulo could drop to around 15ºC, potentially breaking the record low of 16.2ºC set earlier this year on January 11. The forecast for the weekend indicates a maximum temperature of just 22ºC, a stark contrast to the highs of 30ºC experienced earlier in the week.
In the interior of São Paulo, temperatures are expected to plummet by about 8ºC due to the cold front. For instance, in São Carlos, the forecasted high for Thursday is 30ºC, which is expected to fall to around 22ºC, with lows nearing 15ºC. The weather will begin to shift on Friday, with a maximum of 26ºC and a minimum of 19ºC.
The Civil Defense urges residents to prepare for potential emergencies by keeping an emergency kit ready, including water, food, flashlights, and first aid supplies. It is also advised to maintain cleanliness in gutters and drains to prevent blockages during heavy rainfall.
In addition to the alerts affecting São Paulo, the National Institute of Meteorology has also issued an orange alert for parts of Rio Grande do Sul and Santa Catarina, where the risk of storms is high. Rainfall in these areas could reach between 50mm and 100mm per day, with wind speeds up to 100km/h and the possibility of hail.
As São Paulo braces for this significant weather event, residents are encouraged to stay informed through official channels and heed the advice of local authorities. The upcoming days present a challenge as the city prepares for the impact of the cold front, with the potential for severe weather conditions affecting daily life.
With the arrival of this cold front, the combination of high humidity and low temperatures will create a chilly atmosphere, particularly in the first weekend of April. The forecast indicates that the region will experience mild temperatures due to the cold air mass and high maritime humidity, contributing to a damp and cool environment.
Looking ahead, Climatempo notes that additional cold fronts are expected to sweep through the region later in April, which could lead to further drops in temperature. Residents are advised to remain vigilant and prepared for changing weather conditions as the month progresses.
