Extreme Heat: 'Heat Dome', which caused extreme temperatures in Argentina, approaches southern Brazil
This hot air mass caused a rise in temperatures in Argentina and contributed to unprecedented fires in Chile. The south of Brazil is expected to be the region most impacted by this phenomenon.
Cities such as Buenos Aires, Córdoba and Rosário recorded temperatures above 40°C - Photo Reproduction/MetSul
An unusual meteorological phenomenon known as the "Heat Dome" is currently affecting vast areas of South America, bringing with it extreme temperatures that defy historical records. This meteorological phenomenon has caused concern particularly in Argentina, where temperatures have reached alarming levels. According to a forecast released by MetSul Meteorologia, the "Heat Dome" is approaching southern Brazil over the next few days, raising awareness of the risks associated with extreme heat.
As a consequence of this, it is expected that maximum temperatures approach or even exceed 40ºC in cities in Rio Grande do Sul. According to MetSul, this phenomenon has been impacting the state since the middle of last week and is expected to persist for an extended period. The heat "dome" tends to mainly affect the west of the state, with no significant impact on the Southeast, although this region also recorded hot days this week. In Argentina, temperatures have exceeded 40ºC consecutively for more than ten days.
What is the "Heat Dome"?
The origin of the expression "heat dome" goes back to the English term "heat dome". Loosely translated, the phenomenon can also be called a “heat dome”. The "Heat Dome" is a meteorological phenomenon that occurs when a mass of hot, dry air is trapped over a certain region, causing a significant increase in temperatures. This weather pattern can persist for several days or even weeks, resulting in extreme and potentially dangerous weather conditions. This phenomenon develops in areas of high pressure, which prevent the formation of rain clouds. Descending air, moving from top to bottom, makes rain formation even more difficult.
Impact on Argentina
In recent days, Argentina has been severely affected by the "Heat Dome", with temperatures reaching record levels in several parts of the country. Cities such as Buenos Aires, Córdoba and Rosario recorded temperatures above 40°C, overcoming historical limits and placing additional pressure on healthcare systems and infrastructure. The National Meteorological Service (SMN) issued red alerts for ten provinces due to intense heat, mainly in the central, western and northern regions.
In Buenos Aires, maximum temperatures reached 39ºC, an exceptional value for the capital even during the hottest summers. This heat wave has put pressure on the electricity system, resulting in power cuts both in the province of Buenos Aires and in the capital itself. Last Thursday (1st), as reported by MetSul, around 60 thousand users were left without electricity in the afternoon, when thermometers approached 38ºC. To deal with growing demand, the country had to resort to importing energy from Brazil.
Southern Brazil on Alert
In Brazil, the heat wave from Argentina last week is forecast to raise temperatures to 38°C in cities in Rio Grande do Sul in the coming days, with no rain forecast. This prolonged high pressure will result in dry air predominating, gradually increasing temperatures until it becomes a heat wave. A heat wave is characterized when a region experiences temperatures at least five degrees above average for four or five consecutive days.
This is exactly the situation observed, especially in the north of Argentina, part of Paraguay and the west of southern Brazil. The expectation is that the phenomenon will not influence the climate in other regions of Brazil. According to meteorologists, the heat wave is expected to be concentrated mainly in the South. According to them, it is common, at the beginning of the year during the summer, for some cities in Rio Grande do Sul and Santa Catarina to reach temperatures of up to 40ºC. However, the heat wave is expected to remain mainly in these regions. In São Paulo, the heat will be more moderate. The El Niño phenomenon tends to contribute to the formation of this heat wave.
