At least 25 dead in US heat wave as severe storms bring new misery to East Coast

A record-breaking heat wave has killed at least 25 people across the United States, and the crisis is deepening as powerful thunderstorms and heavy rain batter the East Coast, triggering flash flood warnings and spreading further damage.

According to NBC and Bloomberg, at least 25 deaths had been linked to the heat wave as of Sunday, July 5.

New Jersey alone accounted for 22 of those deaths. Most victims were between their 30s and 80s and were found in homes without air conditioning, on the street or inside parked vehicles.

The New Jersey Department of Health warned that the heat wave was "not typical summer heat" and described it as a threat to the lives of "people and animals of all ages."

One heat-related death each was also reported in Illinois, Mississippi and Louisiana.

The heat wave was driven by a heat dome that formed across a broad swath of the country from the Midwest to the East Coast. On July 3, temperatures in New York City climbed to around 38 degrees Celsius, with the heat index reaching 43 degrees, while Washington, D.C., Philadelphia and Boston either broke or approached all-time temperature records.

The extreme heat disrupted Independence Day celebrations, forcing numerous outdoor events to be canceled or scaled back. At the National Mall in Washington, D.C., where festivities marking the nation's 250th anniversary were held, heat casualties mounted and National Guard troops were deployed in an emergency response. The surface temperature of chairs left in the sun reportedly reached 70 degrees Celsius.

As the heat wave began to ease, severe weather moved in.

A cold front pushing down from the north collided with the hot, humid air that remained, spawning powerful thunderstorms and heavy rain that caused flooding and wind damage across the eastern United States.

The National Weather Service issued flash flood warnings for the New York City area as strong thunderstorms that originated in Ohio moved through New York, New Jersey and Connecticut.

Some areas were forecast to see wind gusts of around 95 kilometers per hour and frequent lightning strikes, while Manhattan and Queens braced for up to 100 millimeters of rainfall.

The storms knocked out power to roughly 900,000 homes and businesses, particularly in Michigan, New Jersey and New York, and disrupted service on major rail lines including Amtrak and NJ Transit.

Trees were uprooted and utility poles toppled across the region. A total of 511 wind damage reports were filed across the northeastern and mid-Atlantic United States on Saturday alone.

The National Weather Service said an influx of cooler air from the north would bring some relief to daytime temperatures, but warned that high heat and humidity would persist into the night. It urged the public to remain prepared for both heat-related illness and localized heavy rain.