(Updated 8/23 4:30 PM) - Widespread Moderate Heat Risk is expected across the San Joaquin Valley and adjacent lower foothills (including Lake Isabella) as temperatures range from 100 to 104 degrees from Monday through at least Wednesday. Moderate Heat Risk affects those who are sensitive to heat, especially those without cooling/hydration, and some health systems and industries. A Heat Advisory has been issued for the southern San Joaquin Valley valid from Monday through late Wednesday evening.

Widespread Moderate to Major Heat Risk is expected across the Mojave Desert as temperatures reach up to 108 degrees from Monday through at least Wednesday. Morning low temperatures between 75 and 80 degrees will provide little overnight relief from the heat. This level of heat brings a Major Risk of heat-related illnesses for much of the population, especially those without effective cooling or hydration.

The high pressure ridge will once again sit itself over the West Coast this week. With that, max temperatures will range from 100 to 104 degrees across the San Joaquin Valley, Lower Foothills and the Mojave Desert. Best chances for the heat will be through Wednesday, followed by a return to seasonally average temperatures to end this week.