From Texas Standard:
You may have heard that term ‘heat advisory’ quite a bit during this latest heat wave. It’s a notice the National Weather Service sends out to tell people that they need to take precautions to stay safe in the heat – especially people who work outside.
In the Dallas Fort Worth Area, a heat index of 105 degrees triggers a heat advisory. And the reason it’s 105 degrees has to do with geography and, well, you.