Rare heat wave in October hits Southern California

Triple-digit temperatures returned to parts of the Southland this weekend in an uncommon October heat spell.

Record highs were recorded Friday in Palmdale with 102 degrees and Lancaster’s 101. The previous highs of 1 degree fewer were set in 1980 and 1947, respectively. Paso Robles in the Central Coast region set a record of 106 degrees, besting 105 set in 1987.

A number of places in the Inland Empire also saw record temperatures. Palm Springs registered 110 degrees over 109 set in 1987, and Campo’s 103-degree high was above the 101 mark reached in 1980.

National Weather Service forecasters said Southern California will likely experience several degrees of warming in most areas on Saturday, with temperatures about the same Sunday or potentially a bit hotter.

“As a result, it will become dangerously hot away from the coastal plain,” according to the National Weather Service. “Max temps will rise well into the 90s to around or possibly slightly above 105 degrees in the valleys, foothills and lower mountain locations both days.”

An excessive heat warning will be in effect from 10 a.m. Saturday through 8 p.m. Monday in mountain and valley areas, with some highs possibly reaching 108 degrees. Mountain and foothill areas might see overnight cooling only to the 75-to-85 degrees range.

“There is a high risk for dangerous heat illness for anyone, especially for the very young, the very old, those without air conditioning, and those active outdoors,” according to the NWS. “It will be very dangerous to perform strenuous activities during the late morning through early evening hours, including the weekend. Use extreme caution when hiking or biking anywhere in the warned area, including the popular Santa Monica Mountains.”

Forecasters expected a cooling trend Monday night through Thursday, but some locations may still experience above-normal temperatures.

Inland Empire

Inland Empire cities Rancho Cucamonga, Riverside, Moreno Valley, Fontana, Ontario, San Bernardino and Corona were under an excessive heat advisory until 8 p.m. Monday, according to the NWS.

Hot conditions with high temperatures in the upper 90s to 104 were expected. Overnight lows were forecast in the upper 60s to upper 70s near foothill areas.

Coachella Valley and San Diego County deserts, including Cathedral City, Borrego Springs, Palm Desert, La Quinta, Palm Springs, Indio, Palm Desert Country and Coachella were advised of “dangerously hot conditions” with highs 106 to 112 expected. Low temperatures were expected in the mid-70s to upper 80s, according to the NWS.

A warning was also issued through Monday night for the Santa Ana Mountains and Foothills, with temperatures expected in the 90s.

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