Heat alerts cover more than 125 million Americans as records threatened nationwide
A heat wave spanning the United States has placed over 125 million people under alerts, with daily temperature records at risk in multiple regions and additional air-quality concerns from Canadian wildfires.
More than 125 million people across the United States are under heat alerts as temperatures climb from Southern California to the Northeast. Meteorological services warn that daily high-temperature records could be broken in several northern Plains cities, including Rapid City, Fargo and Grand Forks, as well as in New York locations such as Plattsburgh and Syracuse.
Records already fell on Monday in Bismarck, North Dakota (105°F), International Falls, Minnesota (97°F) and Hibbing, Minnesota (93°F). Rapid City, South Dakota, and Dickinson, North Dakota, tied previous records with 102°F and 103°F respectively.
The heat is accompanied by shifting winds that are expected to transport smoke from more than 800 wildfires burning in Canada into the upper Midwest and Northeast on Wednesday, raising air-quality concerns for millions.
Extreme heat warnings extend from Utah, where Salt Lake City may approach 100°F, to the Upper Peninsula of Michigan. Fargo is under an extreme heat warning with a heat index up to 105, while Detroit faces a heat advisory with a similar index. Throughout the week, the upper Midwest will remain hot and humid, with daytime highs in the 90s and heat indices feeling even higher.
In the Northeast, a heat wave beginning Tuesday is forecast to bring three or more consecutive days of temperatures at or above 90°F for New York City, Philadelphia and Washington, D.C., potentially lasting through Saturday. Heat advisories for Tuesday and Wednesday predict heat indices near 100 across much of the region, with New York City near 100 and Washington, D.C., near 105 on Wednesday. Philadelphia and Trenton, New Jersey, are under an extreme heat warning with indices up to 107.
Southern California remains under heat alerts through Thursday, with coastal valleys expected to reach 85-90°F and interior valleys up to 105°F on Tuesday. Temperatures in downtown Los Angeles could climb to the mid-to-upper 90s, while interior valleys may see peaks of 110°F later in the week.
A separate weather threat includes a level 3 flood warning for south-central Texas, where rainfall could exceed 2 inches per hour and total three-day accumulations may surpass 15 inches in some locations. Additionally, a level 3 severe weather risk is in place for northern New England on Tuesday, with the potential for wind gusts over 70 mph, large hail and isolated tornadoes as a cold front moves southward.