ST. HELENA (CBS SF) -- An intense air war was waged on the north edge of the Glass Fire burn zone Saturday, allowing weary firefighters to extend containment of the massive blaze burning in Sonoma and Napa counties to 15 percent before red flag fire conditions settled in for the night.
Cal Fire Operations Chief Mark Bruton said during his Saturday night briefing that air support was playing a key role on the northern edge of the blaze burning in steep terrain toward Lake County.
"It's really steep, heavy terrain, we have some control lines in there but we have a bit of a lack of resources to really work in that kind of terrain," he said. "We used aircraft to really pound it today. We dropped a lot of retardant to help slow the advance of the fire."
Meanwhile, weather forecasters were keeping on an eye on a front developing in the Pacific that could bring much needed showers to the San Francisco Bay Area next weekend. Of particular interest, National Weather Service forecasters said, were plumes of moisture spinning toward Northern California from Hurricane Marie.
"In general, in looking at trends would say that confidence is increasing for some type of precipitation by next weekend," the weather service said. "Rain amounts all over the board based on if Marie gets ingested as well as where (the) cold front would move onshore. As usual would say the better chances would be North Bay and points northward at this time."
But Bruton said the front will not likely bring the level of rain needed to end the fire season.
"We would need to see something like 4-6 inches (of rain) to change how dry these fuels and make it a game changer," he said. "Is that a possibility? Absolutely not."
By Saturday evening, the burn zone had grown to 63,450 acres as the fire has taken a devastating toll in homes, businesses and wineries. At least 293 homes and 272 commercial building have been destroyed in Sonoma and Napa counties with Cal Fire warning that number will climb as damage estimate teams gain additional access to the burn area.
"Napa County has experienced the loss of 173 single family residences with an additional 57 damaged, and 264 commercial properties lost," Calistoga officials said in a news release Saturday. "Contrary to any news reports, no homes or commercial structures have burned within the Calistoga city limits (with the exception of an unrelated utility shed fire)."
There were 2,611 firefighters manning the fire lines that stretched for nearly 100 miles from north of Calistoga to the outskirts of Angwin to south of St. Helena to the suburbs of Santa Rosa.
"Overnight, crews experienced active fire behavior that included slope-driven runs, flanking, and single tree torching," Cal Fire officials said in a Saturday morning news release. "Downed trees and other dry fuels continue to threaten the fire line."
A Red Flag Warning that had been issued on Thursday, expired Saturday morning but conditions deteriorated during the day and forecasters put in back in place for the overnight hours until 6 a.m. Sunday.
The weather service said winds would be from the northwest from 10 to 25 mph with gusts 25 to 35 mph. Humidity levels would also tumble to 15-to-25 percent with some area dipping to 8-12 percent with little or no nighttime recovery in the hills.
"Fire will spread rapidly due to the combination of hot temperatures, very dry fuels, breezy northerly winds and low humidity," forecasters said.
At his morning briefing, Bruton said firefighters had made great progress in their efforts to keep the flames out of Calistoga and Angwin. An area of concern, however, was in the rugged terrain north of Angwin.
While the winds were relatively calm last night elsewhere, they were gusty in that area.
"About 9 p.m. last night we had a significant gust of wind that threw a lot of embercast, that's a lot of hot embers, across our lines and it did create some spot fires for us," he said. "Crews were able to jump on that but they are still in the process of containing those."
Bruton said the fire also continued to advance toward Pope Valley on its northeast edge. Meanwhile, firefighters were battling to save Both-Napa Valley State Park where flames were very active.
Calistoga officials said early Saturday that "a layer of heavy smoke continues to blanket Calistoga as the mandatory evacuation order continues to be in effect. Air quality within the city remains at hazardous levels."
Roughly 52,000 residents have been forced from their homes and hoping for official word or an images on news reports that will confirm their homes are still standing.
Fire crews, some from Alameda County, were protecting homes and building lines up along Highway 29. Their presence was greeted with appreciation by Angwin area residents like Loyal Hughes.
"There's a truck here, a truck there, a truck on the road over there," Hughes said. "Seems like it is well covered."
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