(CNN) Deadly wildfires roared across California on Monday, forcing evacuations and destroying homes and businesses in their paths. The biggest fires burned in the wine country of Napa and Sonoma counties.

Here's what we know so far, according to California authorities.

• Ten people have died and the number is expected to grow.

• More than 100 people were being treated at Napa- and Sonoma-area hospitals for fire-related injuries or health issues including burns, smoke inhalation and shortness of breath.

• An estimated 1,500 structures have been destroyed and 57,000 acres burned in eight counties.

• A wildfire in Anaheim, in Southern California, has spread to 4,000-5,000 acres and burned at least six buildings.

Photos: Wildfires blaze in California Aerial images showing parts of Sonoma and Napa County that have been hit by wildfires. Hide Caption 1 of 33 Photos: Wildfires blaze in California Colby Clark, left, comforts her mother, Bonnie Trexler, after law enforcement escorted them to Trexler's home in Napa, California, to retrieve medicine and personal items on Wednesday, October 11. Trexler was one of the lucky few in her neighborhood whose home was spared. Deadly wildfires have been tearing through the state, destroying homes and businesses and prompting evacuation orders. Hide Caption 2 of 33 Photos: Wildfires blaze in California Highway Patrol officers go door to door to ask Sonoma residents to evacuate their homes as a wildfire approaches on October 11. Hide Caption 3 of 33 Photos: Wildfires blaze in California Homes are destroyed in the Coffey Park neighborhood of Santa Rosa on October 11. Hide Caption 4 of 33 Photos: Wildfires blaze in California The sign of a Firestone store malfunctions in Santa Rosa on Tuesday, October 10. Hide Caption 5 of 33 Photos: Wildfires blaze in California Damaged winemaking vats and tanks stand in ashes and debris at the Paradise Ridge Winery in Santa Rosa. Hide Caption 6 of 33 Photos: Wildfires blaze in California Smoke clouds the sun from wildfires burning in Santa Rosa and Napa Valley on October 10. Hide Caption 7 of 33 Photos: Wildfires blaze in California Mary Caughey, center in blue, reacts after finding her wedding ring in the remains of her home in Kenwood on October 10. Hide Caption 8 of 33 Photos: Wildfires blaze in California Puddles of melted metal trail away from a burned-out car near Napa on October 10. Hide Caption 9 of 33 Photos: Wildfires blaze in California A TV cameraman inches closer to a burning building at a winery in Napa Valley on Monday, October 9. Hide Caption 10 of 33 Photos: Wildfires blaze in California A firefighting plane helps battle a blaze just north of Tustin on October 9. Hide Caption 11 of 33 Photos: Wildfires blaze in California A historic barn burns in Santa Rosa on October 9. Hide Caption 12 of 33 Photos: Wildfires blaze in California The Santa Rosa Hilton Hotel burns to the ground on October 9. Hide Caption 13 of 33 Photos: Wildfires blaze in California Jim Stites watches as part of his neighborhood burns in Fountaingrove on October 9. Hide Caption 14 of 33 Photos: Wildfires blaze in California Fire burns from an open gas valve near the pool area of a Santa Rosa trailer park on October 9. Hide Caption 15 of 33 Photos: Wildfires blaze in California A man rushes to save his house as a wildfire moves through Glen Ellen on October 9. Hide Caption 16 of 33 Photos: Wildfires blaze in California Kristine Pond searches what's left of her family's home in Santa Rosa on October 9. Hide Caption 17 of 33 Photos: Wildfires blaze in California Police cars block State Route 241 as smoke rises above Orange on October 9. Hide Caption 18 of 33 Photos: Wildfires blaze in California A firefighter douses flames in Santa Rosa on October 9. Hide Caption 19 of 33 Photos: Wildfires blaze in California A woman moves horses in Orange as strong Santa Ana winds blow smoke from the Canyon 2 fire toward them on October 9. Hide Caption 20 of 33 Photos: Wildfires blaze in California A firefighter douses flames at a home in Anaheim on October 9. Hide Caption 21 of 33 Photos: Wildfires blaze in California Traffic backs up as people flee Orange on October 9. Hide Caption 22 of 33 Photos: Wildfires blaze in California Santa Rosa residents sift through the remains of a burned home on October 9. Hide Caption 23 of 33 Photos: Wildfires blaze in California The remains of fire-damaged homes and cars smolder at a Santa Rosa trailer park on October 9. Hide Caption 24 of 33 Photos: Wildfires blaze in California A tent structure built for the Safeway Open golf tournament burns in Napa on October 9. Hide Caption 25 of 33 Photos: Wildfires blaze in California Fire consumes a barn in Glen Ellen on October 9. Hide Caption 26 of 33 Photos: Wildfires blaze in California Smoke rises in the hills east of Napa on October 9. Hide Caption 27 of 33 Photos: Wildfires blaze in California A man passes a burning house in Napa on October 9. Hide Caption 28 of 33 Photos: Wildfires blaze in California The remains of fire-damaged homes are seen in Glen Ellen on October 9. Hide Caption 29 of 33 Photos: Wildfires blaze in California A wildfire burns behind the Sonoma Raceway on October 9. Hide Caption 30 of 33 Photos: Wildfires blaze in California A building burns in Napa on October 9. Hide Caption 31 of 33 Photos: Wildfires blaze in California Flames overtake a building in the Napa wine region on October 9. Hide Caption 32 of 33 Photos: Wildfires blaze in California Two women hug as they watch houses burn in Santa Rosa on October 9. Hide Caption 33 of 33

The fires ignited Sunday night and Monday and spread with alarming speed because of dry conditions, Cal Fire Director Ken Pimlott said at a news conference. More than 20,000 people evacuated, some with little notice.

Jesus Torres of Napa said a neighbor called to tell him the fire was bearing down on his house, CNN affiliate KPIX reported.

"We gathered up a few of our things and our pets and headed out to our car," Torres said. "We could see the sky was turning red. ... We didn't know (about the fire) until the last second. There was smoke all over the area."

The first known fatality occurred as a result of the Redwood Complex fire in Mendocino County, Mendocino County Sheriff spokesperson Capt. Greg Van Patten said. Cal Fire tweeted that two people died in the Atlas Fire in Napa County. The Sonoma County Sheriff's Office said seven people had died in Santa Rosa. No additional details were available.

"That number's going to change," Sonoma County Sheriff Robert Giordano said of the death toll in his jurisdiction. Officers are still searching for people to evacuate and rescue, he said, and "it's just logical" more bodies will be found.

The devastation was significant in Santa Rosa, a town of about 175,000.

The fire left whole blocks of residences in smoking ruins and destroyed landmark buildings like the Fountaingrove Inn, a 124-room hotel; a nearby event center, the Fountaingrove Round Barn; and classrooms at the Luther Burbank Center for the Arts, the Santa Rosa Press Democrat reported.

A large part of the town was evacuated, including Kaiser Permanente Hospital and Sutter Hospital . Authorities imposed a sundown-to-sunrise curfew for parts of the city under evacuation orders.

"I'm lucky," Santa Rosa Mayor Chris Coursey said at a news conference. "My house is fine. My family is fine. My city is not."

A man retrieves belongings from where his house once stood in the Fountaingrove area of Santa Rosa.

More than 100 patients were treated at Napa and Sonoma area hospitals because of fire-related injuries and issues, said Vanessa DeGier, spokeswoman for St. Joseph Health. Santa Rosa Memorial also accepted 12 patients from the two nearby hospitals that evacuated, including expectant mothers, she said.

"Our hospitals are beginning to see patients with injuries incurred as a result of evacuation. This includes victims of car crashes and injuries from falling," a statement from St. Joseph Health said.

Active wildfires in Northern California Source: CALFire as of 5 p.m. ET Monday, October 9

Vineyards threatened

Napa County is dealing with the biggest fires, Cal Fire said. The Tubbs and Atlas fires each cover about 25,000 acres. The Patrick fire west of Napa was at 3,000 acres.

The Nuns fire in Sonoma County covers 5,000 acres, and firefighters also are battling a 1,500 acre fire at Highway 37 and Lakeville Highway in Sonoma.

Alison Crowe, the winemaker for Garnet Vineyards & Picket Fence Vineyards in Napa Valley, said she has not been told to evacuate her home on the western edge of downtown Napa.

"A quarter of my co-workers have been evacuated," she said Monday. "I have friends fighting off fires with hoses in the hills. Thankfully a lot of my friends got out last night."

The main road through the area is still open but the aggressive nature of the blaze worries her.

"It's scary. We feel surrounded," she said.

Crowe estimated two-thirds to three-fourths of Napa's grape harvest has taken place. The 2017 harvest will be remembered for this fire, she said.

"Wine doesn't matter, people matter," she said. "I know that's people's attitude right now."

Perfect conditions for fires

Authorities have not said what caused the fires, but noted that dry conditions made it easy for the fires to spread. October is typically the busiest month for wildfires in California, they said.

Complicating firefighting efforts are low humidity and a lack of resources, Napa County Fire Chief Barry Biermann said.

"As of right now, with these conditions, we can't get in front of this fire and do anything about the forward progress," he said, adding that resources from across California were to begin arriving in the area later Monday.

Gov. Jerry Brown on Monday issued an emergency proclamation for Napa, Sonoma and Yuba counties.

"These fires have destroyed structures and continue to threaten thousands of homes, necessitating the evacuation of thousands of residents," the governor's emergency proclamation said. "These fires have damaged and continue to threaten critical infrastructure and have forced the closure of major highways and local roads."

Flames rise from the remains of a burned commercial building in Santa Rosa, California, on Monday.

The California National Guard has sent three medical evacuation helicopters, six firefighting helicopters and 100 military police personnel to assist local law enforcement.

Winds expected to ease

The fire spread smoke across the San Francisco Bay area and the Anaheim-area fire turned the sky red over Disneyland, according to a social media posting.

Firefighters may get a break from the weather on Tuesday, mainly with decreasing winds.

The National Weather Service in San Francisco on Sunday issued a "red flag warning" for the Bay Area because of current or impending critical fire weather conditions. The warning cited dry, "windy locations through the Napa Valley and northern Sonoma County valleys." Gusts ranging from 35 mph to more than 60 mph were recorded.

Satellite imagery of the #wildfires in #California today captured by the VIIRS instrument DayNight Band. More info @ https://t.co/MPP390W64K pic.twitter.com/7KAvRMh9uT — NOAA Satellites (@NOAASatellites) October 9, 2017

But "winds and the fire weather threat will decrease Tuesday in the north, but a threat will remain in Southern California," the weather service said.

Forecasters said the warning will likely remain in effect because of the warm and dry conditions and the presence of wildfires.

Residents fleeing homes, hospitals

Veronica Ortega was at the Kaiser Permanente Hospital in Santa Rosa when she smelled smoke and saw flames through the window of her fiancé's room on the fourth floor.

The two soon were loaded onto a city bus and shuttled away.

Brian Alexander, a 34-year-old Santa Rosa resident, told CNN about stepping in to help his neighbors as the inferno surrounded his apartment complex.

He drove four neighbors to nearby shelters. As they fled the flames one of them told him, "There's no need to repent. Hell is already here."

"I couldn't live with myself if someone died or couldn't get help and I could have been there to stop it," said Alexander, who packed what he could into his car, eyeing his apartment one final time amid the ash and smoke that burned his eyes and made breathing difficult.

He later drove to Kaiser Permanente Hospital, where he works in environmental services, and began helping the hospital evacuate patients by moving gurney beds to the ambulances and city buses that were ferrying the patients to safety.

Before and After from the #TubbsFire in Santa Rosa using Google Street View. After pic from @KNielsenKPIX. pic.twitter.com/65aHVohJiJ — Bryan Wood (@bryanwx) October 9, 2017

"In a situation like this, it is really important that we be the best we can be," he said. "There was no other option."

They watched home burn

Alyssa O'Gorman and her family fled their home in the nick of time. As the flames closed in Sunday night, they left without a change of clothes. O'Gorman, her parents and her grandfather gathered their animals and were out of the house in minutes.

O'Gorman, a nursing assistant, was driving home from her job when she first spotted flames.

After evacuating the house, which sits at the dead end of a one-lane road in rural Napa County, she and her family watched from a distance as a propane tank exploded and their home's roof caught fire.

If O'Gorman hadn't been coming home from work to wake her family, "we would have been in the house trapped," she said.

Along with Kaiser Permanente hospital, Sutter Hospital in Santa Rosa was also evacuated. Much of a mobile home park behind the Kaiser facility burned, CNN affiliate KPIX said.

In Santa Rosa, the Fountain Grove Inn and Hotel was destroyed and another hotel, the Hilton, was in flames, the affiliate reported.