Aided by a massive C-130 air tanker, Boulder County firefighters are battling a 200-to-300-acre wildfire west of Boulder this afternoon, a fast-growing and "extreme" blaze that has forced the evacuation of 26 households in the foothills and put parts of south Boulder on pre-evacuation notice.

Approximately 931 south Boulder phone numbers have been called with pre-evaucation warnings.

"We're about one ridge over from the city of Boulder," Boulder County sheriff's spokesman Rick Brough said of the fire at an afternoon press briefing.

The fire started near the 1500 block of Bison Drive in the Walker Ranch area around 1:15 p.m. and is believed to have been sparked by lightning, Brough said.

The blaze is now burning toward the northeast, Brough said.

A firefighting helicopter flies above the fire near Bison Drive on Tuesday west of Boulder.
© Jeremy Papasso / Daily Camera
A firefighting helicopter flies above the fire near Bison Drive on Tuesday west of Boulder.
Twenty-six evacuation notices have been issued for Bison Drive and the Pine Needle Notch Subdivision, and an evacuation center has been established at New Vista High School at 700 20th Street near Broadway and Baseline Road.

Flagstaff Road is also closed to all non-emergency personnel. The National Center for Atmospheric Research on Table Mesa Drive just west of Boulder also elected to voluntarily evacuate.

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Pre-evacuation orders have also been issued for the city of Boulder for the area bordered by Dartmouth Avenue to the north, Table Mesa Drive and NCAR to the west and Broadway on the east. Residents in those area should be prepared to leave if they are asked to evacuate.

Fire crews are assembling at Fairview High School in case the wildfire burns into the city.

"This is the structure protection plan," said Jeff Long, battalion chief with Boulder Fire Rescue. "We are staying here in case it takes a turn for the worse. As long as the city is threatened, we'll be here."

The South Boulder Recreation Center's pool has also closed for the day due to smoke.

A heavy air tanker is making slurry drops and several helicopters are are also assisting with the blaze.

Brough said the fire currently is burning in unpopulated, "rough" terrain, and there's spotting out in front of the fire.

Pat Foff, who has lived on Bison Drive for 30 years, said she was preparing to head to the airport for a trip when she heard claps of thunder and then a neighbor told her a fire had started. Just after that, she got the evacuation call.

"I was supposed to

View Flagstaff Fire in a larger mapgo to Salt Lake City and now I'm headed to my daughter's house with two unhappy cats and everything I think might be important in my life."

Foff's daughter Kala Mergrdichian and her housemate Susan Gallagher also had their cars packed as they made their way away from the fire.

"You don't take any chances with this weather," Foff said. "Pray for rain."

Several other fires were also reported in the county between 1:15 and 1:30 p.m., shortly after a small lightning storm moved through the area.

One near Thomas Lane and South Foothills Highway in the Eldorado Springs area is contained, according to Brough.

Fires have also been reported near Greenbriar and Lehigh roads and in the area of Diagonal and Mineral between Boulder and Longmont, but Brough said the Bison Drive fire is the only fire not out or contained at the moment.

Kim Kobel, a spokeswoman with the Boulder Fire Department, said units are on standby should the county need assistance.