Weather Forecast: Fall 2026 Starts with Heat, and the First Intense Cold Snap Already Has a Date
If you were hoping for that cozy, crisp chill right at the start of fall, you’ll have to hold on to that anticipation a little longer. Fall 2026 officially began this Friday, March 20th, but the weather forecast for the coming days points to plenty of heat and a scenario that’s far from what we used to see back in the day.
At least, that’s what the latest weather maps are showing. The season of falling leaves is set to arrive with above-average temperatures across most of the country. You know that famous “chill” that was already starting to make an appearance at the end of summer? Well, it’s taking a break. If you live in the Southeast or Central-West, for instance, you’ll still be facing days where thermometers easily hit over 30°C, as if summer is stubbornly refusing to leave.
Persistent Heat and Spotty Rain
What’s striking about this seasonal shift is the unpredictability. The weather and climate forecast indicates that rainfall will be poorly distributed. While the South and parts of São Paulo might see more consistent rain in the first few weeks, the interior of the Northeast and northern Minas Gerais will continue to face dry conditions. And that’s a concern, because it’s been a while since we’ve seen a reliable, steady rain pattern like we used to.
To give you an idea, when you run the forecast models on the platforms we use to track wind and pressure, the scenarios show a persistent atmospheric blockage. In practical terms, this means a hot air mass gets stuck in place, preventing the cold fronts that typically bring true fall weather from arriving right away.
And the Cold, When Will It Actually Arrive?
The big question on everyone's mind: where’s the cold? Well, I’ve been following the forecast models and the date is on the radar. The first major cold snap of fall, the kind that has you pulling your coat out of the closet and craving a warm coffee in the late afternoon, is forecast to arrive in the first week of April. More specifically, between the 6th and 9th.
During that period, a polar air mass is expected to send temperatures plummeting in the South and cause a major temperature shock in the Southeast. But don’t expect a gradual change. The trend is for us to go from a sweltering near 35°C straight down to 15°C in a matter of hours. This kind of abrupt shift is classic for Brazilian fall, but this year it promises to be more intense.
- South (RS, SC, PR): Heads up! The end of the month already starts with dropping temperatures. Get the blankets and heavier coats ready for the first week of April. Frost could appear in the highland areas.
- Southeast (SP, RJ, MG, ES): The forecast calls for heat to dominate the last days of March. The cold is only expected to arrive with force around April 7th or 8th, bringing that biting, bone-chilling wind.
- Central-West and Northeast: The change will be felt less intensely, but nights will become milder, especially in higher-altitude areas like the Chapada Diamantina and the region around Brasília.
If there’s one thing I’ve learned from tracking the weather - forecast all these years, it’s that Brazilian fall has become a box of surprises. Nothing is quite like it was a decade ago. We have to keep a close eye on the constant updates, because this back-and-forth of hot and cold air masses can easily catch everyone off guard.
So, here’s the tip: enjoy this last weekend of March with that lingering heat, because coming up soon, that intense cold snap is going to knock on the door. And when it does, it won't be just to say hello. It’ll be here to stay. The weather for love? For now, only if it’s a love for blankets, because the weather outside is going to be something else.