Excessive Heat in Orange County Inland, California

Hot conditions occurred across inland Orange County Valleys from July 10-14. Highs reached the upper-80s and 90s each day. The following are the highest temperatures reported during the first portion of the event, and the day on which the peak temperature occurred:

Yorba Linda: 96 (7/12/23, 7/14/23). Yorba Linda ranged from 93-96 through the duration of the event.

Fullerton AP: 93 (7/12/23). Fullerton ranged from 89-93 through the duration of the event.

Santa Ana: 92 (7/12/23). Santa Ana ranged from 86-92 through the duration of the event.

Anaheim tied the record (1990) of 97 degrees on July 13.

After a brief cooldown on July 15 and July 16, temperatures rose again July 17-20. The following are the highest temperatures reported during the second half of the event, and the day on which the peak temperature occurred:

Yorba Linda: 98 (7/19/23, 7/20/23). Yorba Linda ranged from 96-98 through the duration of the event.

Fullerton AP: 93 (7/19/23). Fullerton ranged from 89-93 through the duration of the event.

Santa Ana: 91 (7/19/23, 7/20/23). Santa Ana ranged from 90-91 through the duration of the event.

Anaheim tied the record of 96 degrees on July 17 (2006) and again on July 18 (1992), and tied the record of 98 (2016) on July 20.

A long duration heat wave impacted inland portions of Southern California July 7 to 29 with nearly continuous warnings and advisories. San Diego County public health reported 224 heat related incidents around their network of 23 hospitals. Numerous record highs were broken in the lower deserts where temperatures topped 115 for many days in a row, as well as across the inland valleys and mountains. Overnight low temperatures remained elevated in the lower deserts as lows only fell into the mid-80s to mid-90s, exacerbating the extreme heat risk.

July 2023 was the hottest month on record at Palm Springs.