CLEAR LAKE, Calif. (KGO) -- A massive aerial assault is underway in Lake County as firefighters struggle to slow down the fast-moving wildfire that has exploded in size. Scientists say one of the biggest things fueling the fire is the drought.
Nearly a 1,000 firefighters are trying to prevent the Rocky Fire from spreading. So far, three homes have burned. The blaze is burning southeast of Clear Lake, destroying 18,000 acres in less than two days, that's an area bigger than the city of Palo Alto.
The fire is generating enough smoke to be seen from space and the blaze is only five percent contained as of Friday evening.
It has progressed and is currently moving southwest towards Lower Lake and the east side of Clearlake.
A chance of thunderstorms, cooler temperatures and higher humidity is expected for Saturday.
VIDEO: Fire crews protect power lines from Rocky Fire
"The winds have been changing all day, so the south side of the fire has been active all day," said Cal Fire public information officer Brice Bennett. He said the north side Friday is seeing extreme fire activity as well.
"This is a hot, hot day and the low humidity coupled with that swirling wind has been a great big challenge for us today," Bennett added.
Clear Lake residents are nervous about the growing fire.
"It's been very hot, 106 one day, 108 another day," said Steve Presley, a Clear Lake resident. "Today the winds changed and blew a lot of the smoke into town. It's getting a lot harder to breathe. It's hard to see."
At least 650 residents have been evacuated from their homes as the blaze raged in hills covered in dense brush and oak trees and dotted with ranch homes.
PHOTOS: Smoke from Lower Lake area wildfire seen for miles
The Lake County Sheriff's Office has issued a mandatory evacuation order for the Jerusalem Valley area east of Soda Creek, west of Soda Creek, Bonham Road, Quarter Horse Lane, Mustang Court, Bronco Court, Sunset Court and Morgan Valley Road east of Bonham Road.
Advisories for possible evacuations have been issued for the area east of Highway 53 from Riata Road south of Lower Lake north to Highway 20, which includes Ogulin Canyon. An evacuation advisory is not a mandatory evacuation, but it is strongly recommended.
Shelters have been set up at the Middletown High School and Kelseyville High School.
So far, no injuries have been reported.
Governor Brown Friday declared a state of emergency Friday to bolster the response to the wildfires burning across the state. Eighteen large fires are burning, mostly in the scorched northern half of the state, and the incessant drought is making matters worse.
"They only need a little wind to allow them to burn at an explosive rate," said Daniel Berlant, a spokesman for the California Department of Fire and Forestry Protection.
Crews hope for cooler weather this weekend but fear dry thunderstorms will bring more lightening, which has already sparked dozens of small fires, many along the Mendocino Coast.
Brown said the declaration would help speed up help for thousands of firefighters working to corral the blazes. As part of the order, he activated the California National Guard to help with disaster recovery.
A U.S. Forest Service firefighter was killed Thursday while battling the Frog Fire burning in the Modoc National Forest outside Alturas, California. David "Dave" Ruhl, 38, was a 14-year veteran of the U.S. Forest Service and a native of South Dakota. Brown issued a statement Friday about Ruhl's death.
"Firefighter Ruhl will be remembered for his service and bravery and we extend our deepest condolences to his family, friends and colleagues with the U.S. Forest Service," Brown said.
FIRE LINES HOLDING
Crews battling a fire east of Napa Valley held their ground Friday, more than a week after it started.
The blaze has charred more than 12 square miles in Solano County. The fire is about 45 miles east of Napa's wine county, and vineyards are not threatened.
At least 136 structures are threatened, but evacuation orders have been lifted. It mostly contained, and crews are expecting to have it fully corralled by Monday.
A woman was arrested in connection with a small fire near Groveland, a stop-off point for travelers headed to Yosemite National Park.
The 200-acre fire, about 20 miles from the park's entrance, was partially contained Friday. About two dozen homes are threatened and voluntary evacuations are in place.
Lisa Ann Vilmur was arrested Thursday night for recklessly causing a fire and jailed on $100,000 bail. It was not known Friday if she has an attorney.
In a separate foothills blaze northeast of Sacramento, evacuation orders have been lifted for residents of 50 homes. The fire, which ignited Saturday, burned through more than 3 1/2 square miles and is almost fully contained.
BASS LAKE BLAZE
Residents of 200 homes in the central California community of Cascadel Woods were ordered to evacuate Thursday.
A wildfire burning near Bass Lake for several days spread to more than 6 square miles and is partially percent contained.
Authorities say a boy acknowledged starting the fire by playing with a lighter to burn pine needles in the dry Sierra Nevada. They say the boy faces criminal charges but is not in custody because he and his family are cooperating.