The National Weather Service has issued a heat advisory that will be in effect until Friday night. Heat index values will rise above 100 degrees each afternoon this week, and later this week heat index values could reach 110 degrees. Heat-related illnesses are possible during heat waves like this, especially among people living in un-air-conditioned homes, the very young, the elderly, and those who work outdoors. Additionally, temperatures inside cars can reach lethal temperatures in a matter of minutes.