The National Weather Service has issued a heat advisory from 1 to 8 p.m. Friday.

The advisory will be in effect throughout northwestern Missouri, including the counties of Saline, Pettis, Johnson, Lafayette, Carroll, Chariton, Howard, Randolph, and Cooper in the KMMO listening area.

Heat index values of up to 108 degrees are expected. Residents are advised to drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors.