Stockton may be nearing triple-digit temperatures in October, but the city has actually recorded fewer 100-degree days than usual so far this year.
The city has reached at least 100 degrees on 15 days in 2026, compared with an average of 18 to 19 triple-digit days by this point in the year, National Weather Service Sacramento meteorologist Sara Purdue told Stocktonia.
The figures add context to an unusually hot start to October, as above-normal temperatures continue across Stockton and much of the Central Valley.
Average high temperatures in Stockton during early October are typically in the mid-80s, Purdue said. By the end of the month, the average high falls into the mid-70s.
“There’s currently high pressure over much of the West Coast which is leading to the prolonged higher than normal temperatures,” Purdue said.
Stockton and much of the Central Valley remain under a heat advisory through Wednesday evening, with temperatures forecast to approach 100 degrees in some areas.
Although temperatures are well above normal for this time of year, Purdue said fall heat waves are not unheard of in California.
Daily record highs in Stockton from Oct. 3 through Oct. 8 are all 100 degrees or higher, she said. Current forecasts show some days could tie existing records, but the National Weather Service is not forecasting any new maximum temperature records.
The latest 100-degree day recorded in Stockton occurred Oct. 8, 2024, while the latest 90-degree day was recorded Oct. 27, 2017.
That means warmer-than-normal temperatures remain possible later this month, although the chances of extreme heat decrease as October progresses.
“While chances for warmer than normal temperatures are possible, chances decrease significantly the further into the month we get,” Purdue said.
The current heat is being driven by a broad area of high pressure over the West Coast, which has helped keep temperatures elevated across much of California.
The prolonged heat could increase the risk of illness for both residents and pets. Officials recommend staying hydrated, limiting outdoor activities between 10 a.m. and 7 p.m. and remaining in cool indoor spaces during the hottest parts of the day.
According to the city of Stockton’s cooling center listing, the Arnold Rue, Stribley, Seifert and Van Buskirk community centers serve as cooling zones, providing air-conditioned spaces for residents seeking relief from high temperatures.
The city says cooling center activation depends on temperatures reaching 100 degrees and sufficient staffing. Residents can check availability and find additional cooling resources through 211 San Joaquin or by dialing 211.