Southern California towns are on high alert as the first Santa Ana winds of the season have arrived, igniting multiple blazes across the region. 

The red flag warning put out by the National Weather Service (NWS) Wednesday evening followed a relatively quiet wildfire season so far in California. Only 300,000 acres had burned since Jan. 1, compared to the over one million acres that fires have usually burned by mid-October.

Why are Santa Ana winds so dangerous?

Santa Ana winds blow in from the desert, typically between the months of September and May. The winds bring warmer temperatures and drier air to Southern California. They also greatly increase the risk of wildfires—warm winds coupled with summer drought can often make for a dangerous combination. The January 2025 fires that tore through the Pacific Palisades and Altadena were fueled by Santa Ana wind gusts that reached 100 m.p.h. 

This week’s winds will not be as strong, according to NWS predictions. But that doesn’t mean the area is in the clear. The NWS warned that, if any fires ignite, “conditions are favorable for extreme fire behavior.”

What areas of Southern California are impacted by wildfires? 

The largest fire, named the Henderson fire, erupted Thursday afternoon around Camp Pendleton, a San Diego Marine Corps training base, and had burned through 1,404 acres by Friday morning. Two other fires have burned through 200 acres and 43 acres in Los Angeles county. 

The NWS issued a red flag warning on Oct. 15 for the Los Angeles County San Gabriel Valley forecast zone that will stay in effect until Saturday evening. The most extreme conditions are expected in the Ventura and Los Angeles County valleys and mountains, particularly Santa Clarita, Thousand Oaks, and Simi Valley.

As of Thursday night, Southern California Edison shut off power to tens of thousands of customers. Nearly 90,000 PG&E customers were also left without power. Shutting down power helps stop downed power lines or aging infrastructure from sparking fires. 

If you live in an impacted area, sign up for local emergency alerts, plan for power outages, and avoid any outdoor activities that might ignite sparks like BBQs, campfires, or discarded cigarette butts. 

One Southern California town is even encouraging residents to secure hallowed decorations—the giant skeleton and inflatable pumpkins haunting front lawns. High winds can turn Halloween decorations into hazards,” the city of Pasadena said in a Facebook post. “Secure them before winds pick up.”