Brazil: High temperatures forecast to persist across southern, central, and eastern regions through at least Aug. 27

Forecast models indicate that high temperatures will persist across parts of southern, central, and eastern Brazil through at least Aug. 27. As of late Aug. 21, the National Institute of Meteorology (INMET) has issued red heatwave warnings (the highest level on a three-tier scale) across southern Goias, southern Mato Grosso, most of Mato Grosso do Sul, southern Minas Gerais, most of Parana, southeastern Rondonia, northern Santa Catarina, and most of Sao Paulo. Temperatures of more than 5 C (9 F) above the average for the time of year are forecast for more than five days. Yellow low humidity warnings are in place across the rest of the affected area. Relative humidities of 20-30 percent are forecast. There is a low risk of forest fires and health. Officials could upgrade or expand the alerts as the heatwave develops over the coming days.

The high temperatures may result in increased energy and water demand and a heightened risk of heat-related illnesses, such as heat exhaustion and heat stroke. The extended period of oppressive heat and dry conditions may produce ideal circumstances for wildfire growth throughout the affected areas. Heatwaves also pose a threat to vulnerable groups - such as the elderly, children, pregnant women, and those with respiratory illnesses - due to the increased possibility of heat stroke or heat exhaustion during prolonged exposure to high temperatures. These health risks could also extend to relatively healthy individuals during significant heatwave events. In addition to significantly impacting athletes and those who work outdoors, high temperatures can cause problems for people using mass transit. The lack of air conditioning and cramped vehicles during rush hour may lead to some passengers being hospitalized for dehydration.

Very high temperatures may warp rail tracks and force passenger and freight trains to operate at reduced speeds. Road surface damage is also possible, and overheated vehicles may worsen traffic problems in urban areas where congestion is already a problem. Commercial trucking disruptions might occur, as very high temperatures put more stress on vehicles, making tire blowouts more common. Major flight disruptions are unlikely at regional airports, but general aviation disruptions are possible, and some airfreight carriers could reduce cargo loads. High temperatures could lead to an increased demand for electricity, which might trigger localized brownouts or blackouts, exacerbating hazardous conditions when air conditioning is no longer possible.