Brazil will hit 49c in September this year
In recent days, climate models have consistently indicated a potential temperature record in much of central and southern South America. In reality, as the date approaches, the models are indicating even more intense heat.
For the 26th, the models are predicting up to 49°C in Mato Grosso do Sul and Mato Grosso. But the heat record will affect a large part of Brazil, not just the Midwest. Records are also expected to be set in Paraguay, northern Argentina, and Bolivia.
The models indicate a temperature anomaly of more than 20°C, that is, 20°C above the normal for this time of the year.
In Curitiba, the forecast is up to 39°C (the record in the city is 35°C).
In São Paulo, the forecast is 41°C (the record is 37°C).
In Cuiabá, the forecast is 48°C (the record is 43°C).
In Londrina, the forecast is 44°C (the record is 41°C).
In Campinas, the forecast is 42°C...
You can see the model here: GFS Model – 2m Temperature \(shaded\) for South America | Tropical Tidbits https://www.tropicaltidbits.com/analysis/models/?model=gfs®ion=samer&pkg=T2m&runtime=2023091618&fh=0
A heat dome occurs in areas of high pressure that act like heat domes, having descending air (subsidence). This compresses the air on the ground and through compression heats the column of air. In short, a heat dome is created when an area of high pressure remains over the same area for days or even weeks, trapping very hot air below just like a lid on a pot.
It is, therefore, a physical process in the atmosphere. The masses of hot air expand vertically in the atmosphere, creating a high-pressure dome that diverts meteorological systems - like cold fronts - around it. As the high-pressure system settles in a certain region, the air below heats the atmosphere and dissipates cloud cover. The high angle of the summer sun combined with the clear or few clouds sky heats the ground even more.
Evidence from studies suggests that climate change is increasing the frequency of intense heat domes, pumping them higher into the atmosphere, not unlike adding more hot air to an already heated air balloon. Therefore, several studies point to an increase in the intensity, duration, and frequency of heatwaves in Brazil and around the world.
Never in the history of over a century of global climate observation have so many all-time heat records fallen by such a large margin as in the historic heatwave of late June 2021 in the western North America, an effect of a massive heat dome. It was the second most deadly climate disaster of the year with 1,037 deaths: 808 in western Canada and 229 in the northwestern US.
"This was the most anomalous regional extreme heat event to occur anywhere on Earth since the beginning of temperature records. Nothing compares," said climate historian Christopher Burt, author of the book Extreme Weather. Pointing to Lytton, Canada, he added, "There has never been a national heat record in a country with an extensive period of record and a multitude of observation locations that was surpassed by 4°C," he said. International meteorological record researcher Maximiliano Herrera agreed. "What we saw is totally unprecedented worldwide," he said. "It is an endless cascade of records being broken," he summarized.
A rapid response study from the World Weather Attribution program found that the high daily temperatures observed in a study area covering much of western Oregon, Washington, and British Columbia in June 2021 would have been "virtually impossible without human-caused climate change." The study estimated that it was approximately a 1 in 1000 year event in today's climate, but in a world with 2°C of global warming, which is projected for two decades from now, a similar event could occur approximately every five to ten years.