Red Flag Warning: Wildfire Threat Soars Once Sun Goes Down Sunday Night

SAN FRANCISCO (CBS SF) -- Winds will remain relatively calm through Sunday afternoon, but once the sun goes down, the threat of powerful winds with gusts as high as 70 mph and devastating wildfires will soar across the San Francisco Bay Area hills.

That's the warning from the National Weather Service which has issued a Red Flag Warning and a Wind Advisory for the region beginning later Sunday night.

"Things will change quickly as the dry cold front and associated dry air quickly spill into the Delta region and fans out across the rest of the North/East Bay and quickly passes over the rest of the Bay Area," NWS forecasters said. "In terms of winds, everything is still on track. As is often the case as the sun goes down the winds will increase. Between sunset and the overnight hours the northeast winds will howl across much of the Bay Area."

The Red Flag Warning went into effect for the North Bay Mountains and East Bay Hills at 11 a.m. while it will not go into effect in the Santa Cruz Mountains until 8 p.m. They both will run to Monday morning.

Forecasters said winds will be 25-40 mph with gusts reaching 60-70 mph. If a wildfire should erupt, the gusts will quickly spread large clouds of embers.

For several days, officials have warned that wind conditions will be similar during the deadly 2017 wine country wildfire outbreak and 2019 Kincade Fire.

"But this event looks to be more widespread," the weather service said in its Bay Area forecast. "Another noted difference is the strong east winds over the Sierra region west of Tahoe. During these setups those winds take a straight beeline towards Mt Diablo and then under the right conditions will drop down into the East Bay hills region above the 880 corridor."

Like the those two devastating wildfire events, forecasters warned the biggest threat will likely be in the early morning hours.

"The 2017 wine country and 2019 Kincade peaked between 9 p.m. and roughly 1-3 a.m. at night," the weather service said. "This event may arrive slightly earlier but should any fires start it will be a long night of gusty winds."

In the East Bay Hills above Berkeley, residents were anxiously awaiting what the evening will hold. There is the threat of a planned PG&E power shutoff and Berkeley officials asked local residents to either leave their homes Sunday or packed their bags and be ready to flee at a moment's notice.

Narrow roads in Berkeley's Panoramic Hill neighborhood have officials worried residents won't be able to get out quickly during an emergency.

"We would love to evacuate, but where do we go and it's kind of expensive, and the kids have school on Monday," said Berkeley Hills resident Diana Alberghini. "So it's not exactly that easy to evacuate, we packed a bag, we packed backpacks."

Wildfires are not the only threat. Forecasters said the winds will likely toppled trees and rip off large limbs.

"Wind damage still appears likely overnight as the high momentum wind gusts will take out drought and fire weakened trees/limbs/power poles across the region," the weather service said. "Trash and other debris will whip around and cause hazardous driving conditions."

According to the U.S. Drought Monitor, the vast majority of Bay Area communities are in an area of severe or extreme drought conditions.

Meanwhile, the weather service said San Francisco has received just 0.06 of rain since May 18th -- a span of 158 days. And there are no showers forecast for the rest of the month.

The drought conditions, tinder-dry hills, low humidity and gusty winds are a formula for a wildfire outbreak.

In:
• Wildfires
• San Francisco