Adjacent to the snowy storm in the central U.S., strong high pressure west of the Rockies has funneled strong easterly “Santa Ana” winds into Southern California. These hot winds have led to dangerous fire weather conditions and a series of wildfires.
On Thursday, these offshore winds crashed through the southern California hills, leading to dramatic spikes in temperature and drops in humidity.
Weather Underground’s Jeff Masters describes the abrupt onset of this Santa Ana wind event in Camarillo, California – which is northwest of Los Angeles – the site of the most troublesome blaze:
The hourly observations from Thursday, May 2 at Camarillo show the onset of the Santa Ana winds impressively. The temperature jumped from 54° to 81° between 7 am and 8am, and the wind went from calm to sustained 35 mph, gusting to 43 mph, by 9 am. The temperature Thursday afternoon topped out at 98°–a new record high for the date–and the humidity dropped to a desiccating 4%.
Similar swings occurred to the south in Ramona and Ontario, as illustrated in the graphic below from the National Weather Service.
The Camarillo fire has scorched over 8,000 acres and is just 10 percent contained ABC News reports.
USA Today reports the blaze has reached the Pacific Coast Highway as of this morning.
“Thousands of people have fled the area as the wildfire, which has damaged 15 homes, threatened 2,000 more and 100 businesses in its race toward Malibu,” writes USA Today.
Hot, dry and windy conditions are expected to persist today challenging the hundreds of fire fighters on the scene. But the weather improves dramatically tonight and tomorrow with cool, damp conditions expected – which should allow the fire to be contained.
The wildfires arrived just a day after the release of an outlook issued by the National Interagency Fire Center (NIFC) in Boise, Idaho, predicting an unusually early start to the wildfire season in California due to drought, and low snowpack in the mountains. For more information, see this piece from Climate Central: Drought and Heat May Fuel Early Fire Season in West