It was 108 in Redlands and Loma Linda just before 4 p.m. Monday, and triple-digit temperatures were expected to continue through Friday at least, according to the National Weather Service.
The record high for Aug. 6 was 108 for Redlands in 1997, Miguel Miller of the Weather Service said in a phone interview.
The all-time record for Redlands was 114 on June 17 ,1917, Miller said.
"High pressure centered over the Four Corners Region will build westward and bring very warm weather to our area," the Weather Service advised Monday.
"Southeast flow around the edge of the high pressure system will bring some monsoonal moisture through the week, resulting in a slight chance of thunderstorms each afternoon and evening over the mountains."