Record-breaking October heat wave scorches California
An anomalous ridge drives a prolonged, intense heat wave across central and southern California.
The Weather Prediction Center forecasts October 3, 2026, as the hottest day of a short-range period, with temperatures 8-11°C above normal. An anomalous ridge over the western United States is producing this long-duration October heat wave across central and southern California. Some valleys are forecast to reach approximately 42°C.
Record-breaking temperatures across California
Multiple locations tied or broke daily high-temperature records as the heat wave intensified. Downtown Los Angeles and Long Beach reached 39.4°C on October 2, breaking daily records. Burbank reached 38.9°C and tied its daily record the same day.
The National Weather Service forecast valley highs from the upper 90s to 105 degrees on Friday and 100 to 107 on Saturday. The Los Angeles coast was expected to reach the low to mid 90s, with other coastal areas in the mid to upper 80s on Friday. The warning covers the San Fernando, Santa Clarita, and San Gabriel valleys, the Santa Monica and Santa Susana mountains, Calabasas and Agoura Hills, the Los Angeles inland coast, the Malibu coast, the Palos Verdes Hills, county beaches, and Catalina Island. The Antelope Valley is not included.
Extreme heat warnings in effect
The National Weather Service has issued a complex web of Extreme Heat Warnings and Heat Advisories covering vast regions from the Bay Area to San Diego. Temperatures were expected to run 10 to 20 degrees above normal. The National Weather Service Los Angeles/Oxnard described the episode as a major and long-lasting heat wave.
Various offices issued their warnings on October 2. The Sacramento Heat Advisory continues through October 7. Extreme Heat Warnings for Los Angeles, Ventura, and San Diego counties remain in effect through October 8. Very hot temperatures are likely to continue into the second week of October, possibly requiring an extension of the warnings.
| NWS Office | Advisory/Warning | Valid Through (PDT) | Forecast Max Temperatures |
|---|---|---|---|
| San Francisco/Monterey | Heat Advisory | Oct 4 (extended to Oct 5 for interiors) | 35-39°C (mid-90s to low-100s°F) |
| Hanford | Heat Advisory | Oct 6 | approx. 39°C (103°F) |
| Eureka | Heat Advisory | Oct 3 | approx. 38°C (101°F) |
| Sacramento | Expanded Heat Advisory | Oct 7 | 34-38°C (94-100°F) |
| Los Angeles/Oxnard | Extreme Heat Warning | Oct 8 | Valleys approx. 41°C (105°F), Coast approx. 32°C (90°F) |
| San Diego | Extreme Heat Warning | Oct 8 | Lows in 70s°F, inland valleys lower to mid-70s°F |
Health risks and safety guidance
Heat causes more deaths in the U.S. Annually than floods, storms, and lightning combined, according to Dr. Muntu Davis, the Los Angeles County Health Officer. The NWS Hanford office describes a Moderate to Major risk of heat-related illness for much of the population, especially for those without effective cooling or adequate hydration. Overnight lows were expected to stay above normal, limiting the body's ability to recover.
High-risk groups include older adults, young children, pregnant people, people with chronic medical conditions, people living alone, outdoor workers, athletes, and people without air conditioning. Some common medications can make it harder for the body to handle heat. Neighbors and relatives are encouraged to check on older adults and people who live alone.
Cooling centers with air conditioning, restrooms, and drinking water are available, with locations found on the Ready LA County heat page or by calling 211. Residents are advised to stay indoors from 10 a.m. to 3 p.m., drink water regularly, and wear lightweight clothing. Employers must provide outdoor workers with water, shade, and cool-down rest breaks. A fan alone may not prevent heat illness once temperatures climb into the high 90s.
Overlapping hazards and forecasts
Wind Advisories overlap the heat warnings in several inland zones on October 3, with easterly winds of approximately 25-40 km/h and gusts up to 80 km/h in some areas. A separate Extreme Heat Warning covers the Santa Barbara south coast and interior mountains, with coastal temperatures forecast around 29°C and inland areas near 38°C.
A Heat Advisory is also in effect for portions of San Luis Obispo and Santa Barbara counties, with temperatures forecast around 32°C near the coast and approximately 39°C inland. Residents are advised to check National Weather Service forecasts and county alerts before planning outdoor activities during the week as the Southern California heat wave continues through the weekend with scorching temperatures.
