More than 85 million Americans are under excessive heat warnings or heat advisories, the US National Weather Service (NWS) said Sunday.
Several record highs were forecast to be tied or broken in the US northeast, with heat index values up to 99 degrees Fahrenheit in parts of Pennsylvania, Delaware, New Jersey and Oklahoma, local media reported.
On July 21, a 73-year-old man from Allentown, Pennsylvania succumbed to excessive heat exposure, complicated by underlying medical conditions, according to local officials.
Meanwhile, a 66-year-old woman who had underlying health conditions died of heat on July 22 in Dallas county, Texas.
Hot temperatures in July may have led to dozens of deaths including at least 17 fatalities from Maricopa county, Arizona, weather and medical experts said.
The temperature also caused postponements or adjustments of sports events and delays of trains.
The Boston Triathlon, originally scheduled for Sunday, has been postponed to August 21 while participants competed in the New York City Triathlon with shortened courses on Sunday.
The US National Railroad Passenger Corporation issued multiple alerts from over the weekend on delays of its services in the Northeast due to heat-related speed restrictions.