California faces the first Santa Ana winds of the season

(Trends Wide) — Southern California is facing the first strong Santa Ana winds of this season, which could create conditions conducive to fires and their rapid spread.

Warnings for strong winds have been issued for much of the area, affecting almost 15 million people.

Strong wind watches have been issued for much of Southern California as the Santa Ana winds peak this Wednesday. On the map you can see the areas in red under warning for strong winds and in orange the areas under warning for winds.

“We’re going to have winds of 88.5 to 120 km/h. These are very strong and damaging northeasterly gusts,” Carol Smith, a meteorologist with the National Weather Service in Los Angeles, told Trends Wide. “At the same time the humidity levels will be going down over the mountains, to the valleys and towards the coastal areas.”

From the Santa Monica Mountains and areas to the south, winds will be 40 to 60 mph, with areas on the slopes with potential winds of up to 70 mph, according to Smith.

RED FLAG WARNING!!!

Where: Ventura/LA counties (see graphic).

When: 7 AM to 7 PM Wed

What: Critical #FireWx conditions
– NE wind gusts 60-75 MPH
– RH 6-15 percent

Be prepared and review your evacuation plans. #CAwx pic.twitter.com/PSzQp5EMkt

— NWS Los Angeles (@NWSLosAngeles) November 14, 2022

The low pressure is in the exact location to push strong northeasterly winds into Southern California.

The winds strengthen as they move through the mountain passes and canyons. In the region, winds blow from drier desert regions, and as winds move down the western slopes, the air becomes even hotter and drier. This can quickly absorb any remaining moisture from last week’s rains, which is why the danger is so high even after a wet week.

The region was drenched in rain last week, but according to Smith, it wasn’t enough to extinguish the fire threat.

“Fuels continue to be receptive to rapid fire growth in much of this area,” Smith said. “So with these high winds and humidity levels dropping on Wednesday, any fire that breaks out is likely to exhibit very rapid spread and extreme fire behavior and a clear threat to life and property.”

The Santa Ana winds are forecast to intensify, creating critical fire conditions in parts of California.

San Diego recorded up to 9 inches of rain last week. Although the threat of fire is not as great as in other places, the danger of fires still exists.

“Relative humidity will generally be in the 20 to 25 percent range during the period of strongest winds on Wednesday morning, dropping to 10 to 15 percent during the late morning and afternoon. The combination of strong High winds and low relative humidity will lead to a period of critical fire weather conditions on Wednesday,” the San Diego weather service office said.

One of the biggest concerns is that trees will fall on power lines and start fires. According to Smith, that threat can sometimes trigger preemptive blackouts.

“This is a big cause of fires in our area, which is why a lot of the time, (utilities) do the power shutoffs,” Smith explained. “This is common, although we’re not sure they do it with the recent rains.”

Residents are encouraged to participate in the READY, SET, GO program implemented by Los Angeles County so that people are prepared for events like this. Smith urges people to keep a list and a bag full of documents, medications, supplies for their pets and more.

A Red Flag Warning is in effect for Ventura Co. & much of LA County. Are you READY & SET for wildfire in your area? That means, defensible space around your home, and an emergency supply kit ready in case evacuations are ordered. #CAfire #CAwx https://t.co/sS0kr6lNZe pic.twitter.com/8PjSMPYw9N

— NWS Los Angeles (@NWSLosAngeles) November 15, 2022

Fire conditions should gradually improve by Thursday. But another round of winds could hit the region later in the week. Santa Ana winds most commonly occur during the colder months.

— Trends Wide meteorologists Monica Garrett and Tom Sater contributed to this report.