Dry, gusty winds expected for weekend trigger red flag warning in Sonoma County

Dry gusty winds, unseasonably warm temperatures and the prolonged absence of autumn rains will create dangerous fire conditions in North Bay mountains this weekend, authorities warned Friday.

The National Weather Service issued a rare December red flag warning - indicating extreme fire danger - for Sonoma County, the rest of the North Bay and the East Bay hills from 10 p.m. Friday to 10 a.m. Sunday.

The lack of rainfall, low humidity, dry winds and high temperatures all lead to a “prolonged period of critical fire weather,” National Weather Service Meteorologist Anna Schneider said.

Such warnings are common in the North Bay during fire season but rarely come this late in the year, Schneider said.

“It is not normal, but it is not unprecedented,” she said.

The rainy season has started off slow, with precipitation levels 58 percent of normal around Santa Rosa, Schneider said. There’s a chance of rain midweek, but “the models have been inconsistent, so if that doesn’t happen it won’t rain for a while,” she said.

Adding to the worries, northerly winds blowing at regular speeds of 20 to 35 mph with gusts up to 50 mph are expected for higher elevations this weekend, Schneider said. Winds are expected to be moderate elsewhere.

Even though many on the North Coast felt chilly mornings in the mid-30s, afternoon temperatures have typically increased to around 70 degrees, Schneider said. The mean high temperature for Santa Rosa in December is in the mid-50s.

Fire officials are asking people not to set campfires or even engage in permitted brush burning this weekend.

“You should never start a fire when winds are above 10 miles per hour,” said Cal Fire and Napa County Fire Capt. Chase Beckman.

The Santa Rosa Fire Department has put summertime wildfire equipment back on all engines and trucks in preparation for the weekend winds, said Assistant Fire Marshal Paul Lowenthal. The fire department also has suspended all nonemergency activities that would take equipment out of service for the weekend.

For Lowenthal, the lack of rain this autumn has both helped and hurt conditions in Sonoma County. The absence of heavy rains allayed concerns of erosion and landslides in fire-ravaged areas while also giving hillsides a chance to stabilize. At the same time, trees and brush haven’t received rain needed to reduce the risk of fire.

While areas burned in the October wildfires are less susceptible to reigniting should a fire escape or a utility pole blow over, there are still unburned areas within the fire perimeter that could pose a risk, officials said.

Fire officials don’t expect a repeat of the high and dry winds that buffeted the North Bay on Oct. 8, fueling the rapid spread of numerous fires, but they still urged residents to have an emergency plan ready and sign up for SoCo Alerts and Nixle to receive emergency updates on mobile devices.

You can reach Staff Writer Nick Rahaim at 707-521-5203.