October heat wave breaks several California records, and more expected

An unusual October heat wave — still yet to peak across California — has already set records across the state and brought unseasonably hot weather to cities all across the state from Redding through San Diego.

The triple-digit temperatures in many parts of the state have put millions of Californians under heat advisories lasting through at least Thursday — and even longer in the state’s desert communities near Nevada and Arizona.

“Record high temperatures were smashed today at several locations,” the National Weather Service’s Los Angeles account said on X late Tuesday.

Palm Springs broke several records Tuesday, with its high of 117 degrees setting not only a daily high for Oct. 1, but also marking the city’s highest temperature ever recorded for the entire month, according to the National Weather Service. The city also set a record minimum temperature for Oct. 1, not dropping below 82 degrees, even at night.

Phoenix, which has been sweltering under a much longer heat wave, also set record high for any October day, hitting 113 Tuesday.

In the Central Valley, some daily records were sent Tuesday, but highs Wednesday and Thursday “will be approaching all time October highs,” the National Weather Service said.

These dangerously hot temperatures have increased concerns about fire starts, as well as health concerns.

“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,” the National Weather Service wrote in its heat advisory for parts of Los Angeles area. “Overnight low temperatures will offer little reprieve from the heat.”

Here is a list of locations that set the highest Oct. 1 temperatures on record across California: