While Cal Fire continues not to post any containment level for any of the major fires burning in Napa, Sonoma or Mendocino counties, and fire acreage has remained mostly steady, winds are predicted to kick up Tuesday evening, as the Chronicle reports, and already an extra-loud evacuation warning is being repeated for the Oakmont neighborhood in Santa Rosa, a senior living community that is now under threat from the northern portion of the Nuns Fire, which began in nearby Glen Ellen and has since jumped Highway 12 and, apparently, a ridge line according to the map above.
The Press-Democrat confirms that another neighborhood, Bennett Ridge, which is above Bennett Valley, has lost 75 homes to fire today.
We also have another small fire to talk about, the Pocket Fire, which is being considered part of the Tubbs-related LNU Complex Fire, and has now burned 1200 acres near Geyserville. In total, the LNU Complex Fire is still threatening 16,000 structures.
As for the fires' cause, we are way too early to know anything for certain except that high winds were largely to blame for how quickly they became devastating.
You've likely heard reports about the extremely high winds of 50 to 70 miles per hour that came blasting over ridges in Napa and Sonoma and as far east as Nevada County Sunday night, helping to fuel and possibly spark wildfires in 17 different locales seemingly all at once. Southern Californians are more than familiar with the warm, east-to-west Santa Ana winds that typically arrive in late fall and have been blamed not only for fueling fires but also making people crazy and causing spikes in crime. We have our own, lesser known Northern California version, the Diablo winds, and as the LA Times explains, they come from a similar weather phenomenon, and on Sunday into Monday they were blowing northeast to the southwest.
UCLA climate scientist Daniel Swain calls the geographic spread of this week's fires "jaw-dropping," and he says, "It’s definitely edging up there into one of the worst clusters of fires in California history."
The Diablo winds get created when "air coming down from Nevada and Utah falling from an elevation of about 4,000 feet gets pushed down to sea level, and that air is compressed, and warm winds are created," per the LAT.
Swain suggests that the winds would have felt much stronger up along the hills in Sonoma County, which could explain why down in the valley in Santa Rosa, so many were taken by surprise. "What may have surprised people is that these strong winds didn’t manifest themselves in the cities,” Swain tells the LAT. "But they moved impossibly fast on the ridgeline." Some gusts were up to 70 mph, and what may have just been small brush fires turned into out-of-control, spinning firestorms.
Hopefully tonight's winds are closer to what happened Monday night, and not what happened Sunday night, and by tomorrow we begin to see some containment percentages on these fires and not more reports of lost homes and lives.