Tens of millions swelter as heat wave blasts US

Tens of millions of Americans sweltered under furnace-like temperatures Tuesday as central and eastern cities hunkered down for a heat wave set to last through the July 4 holiday weekend.

Dozens of local temperature records could be broken, the National Weather Service warned, with temperatures in many places to surpass 38 degrees Celsius and high humidity pushing the heat index as high as 46 C.

It comes as America prepares to celebrate its 250th anniversary of independence, and as the United St ...