The massive York Fire that ignited in the Mojave National Preserve is almost fully contained after more than a week of expansion in California and Nevada, according to fire officials.

The wildfire, which started on July 28 in California's San Bernardino County and is among dozens burning around the United States, reached 93% containment as of Sunday, according to an update from Inciweb.

The York Fire occupies an area of 93,078 acres -- mainly in California, where the blaze is the state's largest wildfire this year, CNN previously reported.

Over 9,100 acres are also burning in Clark County, Nevada.

Officials are starting to demobilize excess firefighting resources but said Sunday that "sufficient resources will remain to complete all objectives."

"The joint effort to suppress the York Fire is a testament to the abilities of wildfire emergency resources," according to the update.

Winds picking up during scorching heat aided the fire's crossover into Nevada on July 30 after it initially began in the New York Mountain Range of California's Mojave National Preserve two days prior.

Though firefighters were able to gain some control over the blaze over the past week, their efforts were hindered by extreme conditions as its rapid growth made it tough to control, fire officials said.

Firefighters reported the sight of a phenomenon called fire whirls -- a spinning column of fire made from a vortex of smoke and flames -- as a result of intense heat and turbulent winds combining, according to the Mojave National Preserve.

Park officials noted the unpredictable nature of fire whirls, which can rise as high as several hundred feet and can suddenly change direction with varying speed.

"These fire whirls are similar to dust devils but are specifically associated with the heat and energy released by a wildfire," the Mojave National Preserve said.

Dry air and falling humidity levels filtering back into the region could pose additional challenges to firefighters working the blaze, according to the Inciweb update Sunday.

As of August 4, over 31,300 wildfires across the country have scorched 1.2 million acres since the start of 2023, according to the National Interagency Fire Center.