With "feels like" temperatures expected to be in the triple digits on Monday, the National Weather Service has issued a heat advisory for South Florida.

All of Florida will be under heat advisories Monday, July 21, as a heat dome spreads from the Ohio and Mississippi valleys. Here's what to know.

The heat index considers the actual temperature and amount of moisture in the air using the dew point or relative humidity.

The National Weather Service says heat indices as high as 114 are possible in Panama City and issued an advisory. Meanwhile an Atlantic system brews.

Update: Here are the top stories we're following around the Big Bend, South Georgia, Nationally, and your Tuesday forecast.

The chances for a scattered area of showers and thunderstorms to develop into something more increased overnight, but remain low, forecasters said.

The National Weather Service office in Mobile, Alabama, issued a heat advisory in Escambia, Santa Rosa and Okaloosa counties between 10 a.m. and 7 p.m. Monday. Heat index values are forecast to reach as high as 109℉ in portions of south central and southwest Alabama, northwest Florida and southeast Mississippi.

How low should you set your thermostat for as record-breaking heat sweeps over the country? Here's what experts and other Floridians say.