00:52 Northwest Dries Out and Turns Hot Meteorologist Heather Tesch takes a look at a pattern change for the Northwest.

At a Glance Pacific Gas and Electric started shutting off power early Wednesday morning.

Santa Clara County declared a state of emergency because of the power shutoffs.

One city announced a curfew for Wednesday night as well.

PG&E power lines have been blamed for several high profile fires in recent years. Power is being shut off to nearly 800,000 Pacific Gas & Electric customers in Northern California due to the threat of wildfires, and in some areas, officials declared emergencies and curfews to deal with the blackouts.

A state of emergency was declared for Santa Clara County as the area prepared for additional outages on Wednesday, according to KRON-TV. Meanwhile, in the city of Morgan Hill, a curfew was in place from 7 p.m. Wednesday night until 6:30 a.m. Thursday as authorities worked to reduce the possibility of crime in blackout areas, according to the Associated Press.

Driving is permitted during the curfew in the city of about 45,000, the report added.

Schools and universities were closed in some areas and residents stocked up on groceries, batteries and gas ahead of the blackouts, which PG&E said could last as long as five days.

(MORE: California's Fire Risk Is Highest in the Fall, and This Week Is No Exception)

Some 540,000 homes and businesses in northern California were already without power as of 7:30 p.m. EDT Wednesday, according to poweroutage.us. PG&E's website had crashed due to high traffic.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/firedanger_0.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/firedanger_0.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/firedanger_0.jpg?v=ap&w=980&h=551 800w" > The National Weather Service has issued fire alerts across much of California, prompting Pacific Gas and Electric to shut off power to some 8,000 customers. (NOAA)

The preemptive outage stands to be one of the largest in the state's history as windy, dry conditions raise the risk for wildfires in the coming days. Many of those affected are in the San Francisco Bay area and the northern part of the state, including San Jose, Oakland, Fremont, Santa Rosa, Hayward, Berkeley and San Mateo.

The shutoffs started at 12 a.m. PST Wednesday morning, with the first phase expected to impact about 500,000 customers in 22 counties, PG&E said in a news release.

A second phase was expected to start at noon with another 230,000 customers affected, but PG&E announced that the shutoffs would be delayed until later in the day. A third phase covering about 40,000 customers is also being considered.

In all, parts of some 34 counties in northern, central and coastal California face blackouts. The utility said the shutoffs were being considered based on a fire weather watch from the National Weather Service. Winds up to 65 mph were expected in some areas, prompting the NWS to issue alerts for elevated, critical and extreme wildfire chances across large swaths of the state.

Windy conditions can cause power lines to spark fires when they are blown down, or to come into contact with trees or other vegetation. PG&E power lines have been blamed for several high profile fires in recent years, including the blaze that killed 86 people last year in Paradise, California.

Researchers have such said catastrophic fires could become more common as climate change leads to warmer weather and longer fire seasons.

(MORE: The Science Behind Wildfire-Stoking Santa Ana Winds)

While the outages will impact 800,000 PG&E accounts, many more actual individuals could be affected. Millions could face days without electricity, the San Francisco Chronicle estimated.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/AP19282504267117.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/AP19282504267117.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/AP19282504267117.jpg?v=ap&w=980&h=551 800w" > Armando Espinoza delivers paper products to a cafe in downtown Sonoma, California, where power was turned off, on Wednesday, Oct. 9, 2019. (AP Photo/Noah Berger)

Hospitals, municipalities and other agencies across the affected areas were prepared to have generators on stand by and were warning residents to stockpile supplies. Those who use medical equipment that relies on electricity were being warned to prepare for the outages and call for assistance if needed, and residents were being told to have go bags and emergency kits on hand.

Local police departments were warning drivers to beware of nonfunctioning traffic lights.

Elected officials and residents expressed anger over the blackouts.

"People should be outraged, as we are," said California Gov. Gavin Newsom. "No one is satisfied with this. No one is happy with this. But we have to get through this fire season."

Newsom has called on PG&E to upgrade infrastructure to make it less vulnerable and prevent massive outages such as this one.

Oakland Mayor Libby Schaaf asked residents not to flood 911 lines with non-emergency calls, the AP reported. The city canceled all days off for police officers days in preparation for the outages.

"We all know the devastation that fires can cause," Schaaf said.

PG&E says safety is its first priority.

"This is a last resort," Sumeet Singh, head of the utility's Community Wildfire Safety Program, told the Chronicle.

At the Dollar General store in Paradise, the town that was mostly burned to the ground by the Camp Fire, shoppers were grabbing candles, gas cans, ice, flashlights, batteries and canned food. Ice chests were sold out Tuesday morning, manager Ben Humphries told the AP.

Humphries, who lost his home in last year's blaze, saw some irony in PG&E's aggressive preemptive power outages in the area now, after the company opted not to turn off the power ahead of the Camp Fire.

"I understand their concerns. But in my opinion, it's too little too late. We already had our town burned to the ground," Humphries said.

In addition to the 800,000 or so PG&E customers who could be impacted, more than 100,000 Southern California Edison customers in eight counties could also see preventive outages in southern portions of the state, according to the AP.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/util/image/w/gettyimages-1175085302.jpg?v=at&w=485&h=273" srcset="https://s.w-x.co/util/image/w/gettyimages-1175085302.jpg?v=at&w=485&h=273 400w, https://s.w-x.co/util/image/w/gettyimages-1175085302.jpg?v=ap&w=980&h=551 800w" > 1 of 29 A customer peers in a closed Safeway grocery store which is closed after the power was shut down as part of a statewide blackout in Santa Rosa, Calif., on Oct., 10, 2019. Rolling blackouts set to affect millions of Californians began Oct. 9, as Pacific Gas & Electric started switching off power to an unprecedented number of households in the face of hot, windy weather that raises the risk of wildfires. PG & E, which announced the deliberate outage, is working to prevent a repeat of a catastrophe last November in which faulty power lines it owned were determined to have sparked California's deadliest wildfire in modern history. (Josh Edelson/AFP via Getty Images)

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