With parched vegetation and one of the strongest Santa Ana wind events in years expected to sweep through Southern California this week, the region is bracing for the type of weather that can help wildfires spark and spread quickly and easily.
Forecasters on Monday warned that they expected “life-threatening and destructive” winds to combine with dry air, creating a critical fire-weather event in Southern California in the coming days. In addition to the fire risk, widespread damaging wind gusts, reaching 50 to 80 miles per hour, and even above 100 m.p.h. in the mountains, may knock down trees and power lines.
In anticipation, utility companies that serve the region warned they could begin shutting off power to some customers, though none had done so yet on Monday. San Diego Gas and Electric Company said it was considering power shut-offs for more than 64,000 customers as early as noon on Tuesday. Southern California Edison said it was considering cutting off nearly 300,000 customers, one of its largest pre-emptive outages ever.
These winds aren’t unusual, and the strongest Santa Ana winds typically happen this time of the year. But by January, Los Angeles has usually had enough rain that the fire threat is mitigated because the vegetation is greener and there is more moisture in the ground. This year, that hasn’t been the case, said Rich Thompson, a meteorologist with the National Weather Service in Los Angeles.
Because the vegetation is extremely dry, if a fire starts, these winds will help it spread rapidly — just as the Mountain fire did in November across Ventura County and the Franklin fire did in Malibu in December. “Any spark, any ignition source, could lead to something very, very dramatic, very, very quickly,” Mr. Thompson said.
After a short-lived dip in speed on Tuesday afternoon, the winds are expected to accelerate to dangerous levels from Tuesday evening into Wednesday morning. Gusty winds and dangerous conditions could linger into Thursday or even Friday.
The weather conditions will mostly be similar to those that led to the Mountain and Franklin fires. However, in a few areas, winds may reach stronger levels than during those earlier events.
The longer-lasting strong winds will occur mostly across Los Angeles and Ventura Counties. Moderate to strong winds may even reach the Los Angeles County coast, especially in the Hollywood Hills, Beverly Hills and Sepulveda Pass, and extending into Palos Verdes and Catalina Island from Tuesday evening into Wednesday, according to forecasters in the Los Angeles National Weather Service Office.
Even portions of the San Gabriel Valley and the San Fernando Valley, which don’t often see damaging wind gusts, could see strong winds during this event’s peak.
The winds may return next week. “We’re not catching a break,” Mr. Thompson said. “There’s just no rain in the forecast. So this is going to be a persistent issue for the next couple of weeks.”
Jesus Jiménez contributed reporting from Los Angeles.
