Firefighters took advantage of cooler temperatures and a light drizzle Tuesday as they stepped up containment of the 67,000-acre Rocky fire, establishing solid lines around 20 percent of the blaze during what was the calmest day for crews since the fire began a week ago.
The progress was considered a big break in the battle against the state’s largest blaze, which until Tuesday had been nearly uncontrollable, racing over rural properties and wildland, burning more than 50 structures, and as late as Monday, jumping a major highway firefighters had hoped to use to halt the advance.
The fire burned an additional 3,000 acres Tuesday, expanding in the wildland north of Highway 20 near where it jumped the road Monday afternoon.
After the exponential growth at the fire’s perimeter over the weekend, fire officials signaled they were content with the gains Tuesday.
“The weather is cooperating and acreage is not going up significantly,” said Paul Lowenthal, a Santa Rosa assistant fire marshal who is supervising public information officers on the wildfire. “The fire activity has been relatively calm for a full day for the first time.”
Still, there were signs in the sky late Tuesday that worried fire commanders, with thunderstorms expected during the night, raising the possibility that lightning could fuel additional fires in the area. Firefighters were heading out late Tuesday to strengthen fire lines.
“We’ll probably have lightning tonight through (Wednesday). That kind of weather makes people nervous up here,” said David Cornelssen, a battalion chief for Central Fire in Windsor.
Cornelssen has been leading a crew of 21 Sonoma County firefighters on the effort, and Tuesday evening they were headed to their all-night assignment along Highway 20.
“All the hard work that’s been put into it to get it where it is ... It would all be for naught” if lightning sparked more fires in the area, Cornelssen said.
The Rocky fire is one of almost two dozen wildfires burning in California. Almost 3,500 firefighters are working the blaze, including about 100 personnel from Sonoma County’s fire agencies.
Containment Tuesday morning started at about 12 percent. By evening, another survey showed that figure was up to about 20 percent, Cal Fire officials said.
No additional buildings were lost Tuesday, leaving the number of homes destroyed at about two dozen. Another two dozen outbuildings, such as barns, also were lost earlier in the fire.
Mandatory evacuations remained in place Tuesday night for rural communities including Spring Valley, northwest of the fire. About 1,200 people had been ordered out of their homes and another 10,000 or so were warned they should leave the area because of the fire’s location.
The advisory evacuation orders included the largest city in the area, Clearlake, as well as the town of Clearlake Oaks.
Forecasts Tuesday initially called for gusts of 15 to 20 mph from the east, leaving fire officials worried the flames would push closer to Clearlake in the same way they had encroached on Lower Lake days before. Evacuations of Clearlake, home to nearly 15,000 people, would have become mandatory in such conditions, Lowenthal said.
But the winds didn’t materialize and cooler temperatures with thick cloud cover even generated a light drizzle, offering firefighters a break in the heat, including days of 100-degree highs that have fueled the blaze.