It’s been back-to-back heat advisories for South Florida as the National Weather Service issues the fifth heat advisory this week. This time the heat advisory will be in effect in Miami-Dade and Broward counties on Saturday from 10 a.m. to 6 p.m. with an expected heat index, the temperature when you mix in humidity, of 104-106°F. In the Florida Keys, the heat advisory will be in effect from 10 a.m to 7 p.m, with temperatures feeling up to 110°F.