A fast-moving wildfire has engulfed a Northern California town, levelling much of the central business area as well as several homes.

The Dixie Fire tore through the Greenville on Wednesday evening, destroying properties and casting the sky in an orange glow.

A photographer described seeing a petrol station, hotel and local bar burned to the ground in the town of 800 people.

A firefighter
A firefighter uses a drip torch to ignite vegetation while trying to stop the Dixie Fire from spreading (AP)

The three-week-old fire has grown to over 428 square miles across Plumas and Butte counties.

“If you are still in the Greenville area, you are in imminent danger and you MUST leave now!!” the Plumas County Sheriff’s Office posted on Facebook earlier on Wednesday.

Firefighters had been trying to protect the town of 800 about 280 miles north-east of San Francisco by clearing debris from roads and marking hazards.

Pandora Valle, a spokesperson with the US Forest Service, earlier told The San Francisco Chronicle that “firefighters are fighting for the town of Greenville”, but could not provide further details about the damage.

A burnt-out car
Following the Dixie Fire, a scorched vehicle rests in a driveway in the Indian Falls community of Plumas County (AP)

The destruction came amid a red flag warning issued by forecasters warning over hot, bone-dry conditions with winds of up to 40mph.

That could drive flames through timber, brush and grass, especially along the northern and north-eastern sides of the vast Dixie Fire.

“I think we definitely have a few hard days ahead of us,” said Shannon Prather of the US Forest Service.

Firefighters were able to save homes and hold large stretches of the blaze.

The Dixie fire
The Dixie fire has grown to 428 square miles (AP)

However, flames jumped perimeter lines in a few spots on Tuesday, prompting additional evacuation orders for about 15,000 people east of Lake Almanor, fire officials said.

Heat from the flames created a pyrocumulus cloud, a massive column of smoke that rose 30,000ft in the air, said Mike Wink, a state fire operations section chief.

The fire has threatened thousands of homes and destroyed 67 houses and other buildings since breaking out July 14. It is 35% contained.

About 150 miles to the west, the lightning-sparked McFarland Fire threatened remote homes along the Trinity River in the Shasta-Trinity National Forest. This blaze is was only 5% contained.

It has burned fiercely through nearly 25 square miles of drought-stricken vegetation.

Similar risky weather was expected across Southern California, where heat advisories and warnings were issued for interior valleys, mountains and deserts for much of the week.

Heat waves and historic drought tied to climate change have made wildfires harder to fight in the American west. Scientists say climate change has made the region much warmer and drier in the past 30 years and will continue to make weather more extreme and wildfires more frequent and destructive.

More than 20,000 firefighters and support personnel are battling 97 large, active wildfires covering 2,919 square miles in 13 US states, the National Interagency Fire Centre said.

On Tuesday, Montana had 25 active large blazes, followed by Idaho with 21 and Oregon with 13. California has 11.

In Hawaii, firefighters gained control over the 62-square-mile Mana Road Fire that forced thousands of people to evacuate over the weekend and destroyed at least two homes on the Big Island.

Oregon’s Bootleg Fire, the nation’s largest at 647 square miles, is 84% contained. Firefighters were busy mopping up hot spots and strengthening fire lines.