» Weather Section » Sign Up For Breaking News Alerts» Like Us On Facebook» Follow Us On Twitter

"Hot conditions will continue through Friday, with gradual cooling in the coastal zones Saturday before spreading into the western valleys on Sunday," according to the National Weather Service.

The agency attributed this week's heat wave to high pressure over the southwest states.

"Although some cooling will begin this weekend west of the mountains, the deserts will remain very hot through Sunday," according to an NWS advisory.

An excessive heat warning remains in effect until 8 p.m. for deserts areas, where the NWS forecast daytime highs between 108 to 118 degrees, with heat index values of 112 to 122 and overnight lows of 85 to 95. The heat index values factor in the humidity to determine how hot it really feels.

"Hot days followed by warm and humid nights can limit the body's ability to keep cool," according to an an NWS advisory. "Visiting hikers and campers unfamiliar with intense desert heat are especially susceptible to heat stroke or heat exhaustion. Pets are also susceptible to this heat."

Daytime highs in mountain areas will range from 100 in the foothills to the mid-80s above 6,500 feet. There's also a slight chance of afternoon showers and thunderstorms in the mountains through Monday, NWS forecasters said.