The National Weather Service has issued an Excessive Heat Warning for parts of Northern Arizona for Saturday through Monday. The warning is in effect from 10 a.m. Saturday through 8 p.m. Monday for areas below 45-hundred feet. The warning includes Cottonwood, Camp Verde and other lower elevations of Yavapai County. Forecasters say extreme heat will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances.