New Delhi, July 6 -- The Fourth of July celebrations marking America's 250th anniversary were marred by deadly storms and a heat wave across large parts of the United States, leaving hundreds of thousands of utility customers without electricity. Forecasters have also warned that severe weather is expected to continue through the week.

CBS News on Sunday (local time) reported that millions of Americans across the Northeast experienced record-setting temperatures, while thunderstorms in the Midwest toppled trees, brought down power lines, and disrupted travel across several states.

In the capital city, Washington, D.C., thunderstorms compelled thousands to temporarily evacuate the National Mall, which was hosting the Freedom 250 Fourth o...