CNN | A dangerous heat wave is intensifying in the South with more than 55 million people under heat alerts

(CNN) — More than 55 million people from southern Arizona to the Florida coast are sweltering under a worsening heat wave that is expected to expand its reach this week, bringing more dangerous triple-digit temperatures.

Excessive heat warnings, the highest criteria of heat alerts, include Dallas, New Orleans and Baton Rouge, Louisiana, where the heat index will approach 120 degrees.–read more–