By Reginald Stanley. Posted July 18, 2023, 1:42 PM.

The National Weather Service has issued an Excessive Heat Warning for all inland valleys of Southern California, as well as the mountains and deserts, through 8 PM Saturday as a high pressure ridge over Arizona and New Mexico expands westward.

High temperatures in the valleys have been nearing or exceeding 100 degrees in recent days, and is forecast to escalate even higher Thursday through Saturday. Warm overnight temperatures, primarily in the upper 60s and 70s, provide little relief from the excessive daytime heat. The National Weather Service warns that the extreme heat poses a significant risk for heat-related illnesses, especially for those working outdoors or participating in outdoor activities. Such conditions allow car interiors to reach deadly temperatures in a matter of minutes. The National Weather Service strongly advises people to drink plenty of fluids, remain in air-conditioned rooms, stay out of the sun, wear lightweight and loose-fitting clothing, and reschedule any strenuous outdoor activities to the early morning or evening. Relatives and neighbors should be checked on as well.

A slight chance of thunderstorms in the mountains and deserts is predicted for early next week as monsoonal moisture returns to the region. Long-range forecasts do not indicate any significant relief from our current heat spell for the time being.