The Tri-Cities is in for three days of temperatures topping 100 degrees, according to the National Weather Service.
It has issued a heat advisory through Friday.
The high is expected to be 102 degrees Wednesday and 103 degrees Thursday and Friday.
Limited relief from the heat is expected overnight, with lows dipping only to the mid 60s.
Temperatures will cool only slightly for the weekend, with highs forecast in the upper 90s.
The combination of high temperatures and low humidity increases the likelihood of heat exhaustion or more serious heat stroke, says the weather service