Heat Advisories Blanket Southern US as Temperatures Soar

National Weather Service issues warnings from Texas to South Florida with heat indexes reaching dangerous levels.

Temperatures in Miami reached the low 90s Fahrenheit before noon, with heat advisories in effect.
Excessive heat warnings cover northeastern Texas, Oklahoma, northern Louisiana, and most of Arkansas.
Cooling centers have been opened in cities like Dallas, Houston, and Memphis to provide relief.
Meteorologists attribute the extreme heat to a high-pressure 'heat dome' over the southern Gulf of Mexico.
Public advised to stay hydrated, wear light clothing, and check on vulnerable individuals and pets.