The National Weather Service in Oxnard warned of “extremely critical and extremely volatile” fire weather conditions in parts of Los Angeles and Ventura counties, with dry, damaging winds forecast for Wednesday.

The phrase “particularly dangerous situation” was added to a red flag warning — language the weather service reserves for only the most extreme fire danger. The red flag alert was scheduled to begin at 2 a.m. on Wednesday, and the particularly dangerous situation began at 9 a.m. The particularly dangerous situation should last until 4 p.m. on Wednesday on the beaches and in the valleys and until 9 a.m. on Thursday in the mountains.

Cities listed in the particularly dangerous warning include Santa Clarita, Thousand Oaks, Simi Valley, Oxnard, Ventura, Malibu, Burbank and Glendale. Increased fire weather was also predicted in Northern California – including parts of the Bay Area and Central Valley – although the risk was relatively lower than in Southern California. The warning alerts were scheduled to go into effect Tuesday afternoon and last through Thursday morning.

Residents can check their address below to see if they are affected.

In Southern California, the strongest Santa Ana wind event in four years was expected. In Ventura and Los Angeles counties, forecast wind gusts exceeding 70 mph combined with relative humidity in the low teens to single digits are expected to result in “extremely critical fire weather conditions on receptive fuels,” according to the weather service. If fires occur, there is a risk that they will spread extremely quickly.

It has been nearly four years since the Oxnard Weather Service last issued a particularly dangerous warning in December 2020.

“These are very volatile conditions for wildfire spread,” said Ariel Cohen, the meteorologist in charge at the weather service’s Oxnard office.

According to Cal Fire, there were no ongoing wildfires in Ventura County as of Tuesday morning, only the smoldering bridge fire in Los Angeles County.

To prevent new fires from starting, Southern California Edison had planned outages for more than 55,000 customers in high-risk areas. The utility also considered turning off power to an additional 164,000 customers.

Pacific Gas and Electric Co. announced planned power shutoffs for more than 20,100 customers in Northern California. A complete list of planned outages can be found on PG&E's website and on the Chronicle's outage map.