A heat wave, described as “extremely dangerous” by the weather services, is sweeping through the western United States and much of the southern United States this weekend. The mercury will reach up to 47°C in some cities.
“An oppressive and extremely dangerous heat wave is expected to hit the West this weekend, as well as parts of the South,” the National Weather Service (NWS) warned in a Saturday morning bulletin. “Multiple temperature records are likely and air quality issues will be common in many parts of the United States,” the NWS further estimates.
And respite isn’t likely to come anytime soon for the more than 90 million Americans under high temperature alert, as the heat dome is expected to “remain stationed over (these regions) for the next several days.” », Provides the NWS.
In Phoenix, a metropolis of Arizona in the southwestern United States, 47°C are expected at the end of the afternoon for what should be the 16th consecutive day of maximums above 43°C. Part of the state is in Alert Level “Magenta,” a “rare and/or long-lasting extreme heat level” that represents the highest alert level in the NWS. In southern California, firefighters have been fighting several very violent fires since Friday which have ravaged more than 1,214 hectares and led to the evacuation of the population.
For climatologist Daniel Swain of the University of California, Los Angeles, mercury in Death Valley could match or even exceed the highest air temperature ever reliably measured on Earth, 54.4 °C recorded in the same place in 2020 and 2021, according to several experts.
Other regions of the United States are at risk of severe weather. “Strong to severe thunderstorms, heavy rain and flooding are possible in many locations, particularly and unfortunately in New England, already saturated” by recent rainfall, according to the NWS.
This region of the northeast of the country, and particularly the state of Vermont, was affected this week by “historic and catastrophic” floods, the result of torrential rains. In Canada, the number of fires continues to increase, particularly in the west of the country, where in a few days several hundred fire starts have been recorded, mainly triggered by thunderstorms.
And the situation is not going to improve with “hot and dry weather expected in the coming months”, Sarah Budd of the BCWS told AFP: “We don’t expect any respite from the weather. More than 9.7 million hectares have already gone up in smoke across the country – eleven times the one-year average of the past decade. The absolute annual record – dating from 1989 – has already been largely exceeded.
Smoke from the fires in Canada once again sent columns of smoke towards the southern neighbour. Several northern US states, such as Montana and North Dakota are experiencing “adverse” levels of air quality.
Greenhouse gas emissions are increasing the strength, duration and rate of repetition of heat waves, experts say. According to the U.S. Environmental Protection Agency, “heat waves are occurring more frequently than before in major cities across the United States.”
“Their frequency has increased steadily, from an average of two heat waves per year during the 1960s to six per year during the 2010s and 2020s,” she said.
