Parts of the United States and Canada are experiencing another significant heatwave, with extreme temperatures and deteriorating air quality expected to continue into Wednesday. The high temperatures are impacting cities from Toronto to Boston, New York City, Philadelphia, and as far west as Buffalo.
This latest heat event follows a record-breaking heatwave in early July that affected large portions of the U.S., leading to widespread disruptions and significant health impacts. During that earlier event, more than 165 million people experienced record temperatures, and at least 44 deaths across the U.S. were attributed to the heat.
A powerful area of high pressure has settled over the upper levels of the atmosphere, extending across the U.S. and parts of Canada. This mass of hot, humid air, described as a dome, has already caused all-time temperature records to be broken in areas like Montana and Utah before shifting eastward.
The Midwest and Northeast regions of the U.S. are expected to bear the brunt of the current heat. Chicago is forecast to reach 97F (36C) on Wednesday, while New York could see temperatures climb to 100F and Washington D.C. anticipates 102F. High humidity levels are expected to make these temperatures feel even more intense.
In Canada, central and eastern areas have also experienced high temperatures. However, a cold front is anticipated to bring cooler temperatures in the coming days, along with the possibility of severe thunderstorms. These stormy conditions may also spread into parts of New England.
By the weekend, these thundery conditions are expected to become more widespread across eastern North America, helping to push back the most extreme heat. Nevertheless, temperatures in many areas are predicted to remain above seasonal averages. The disruption caused by extreme heat was evident earlier this month when the Fourth of July parade in Washington D.C. was canceled due to the conditions.
Scientists attribute the increasing frequency, intensity, and duration of heatwaves to human-induced climate change. Global temperatures have already risen by approximately 1.1C since the beginning of the industrial era, and further warming is expected unless significant global emissions reductions are implemented.