FIREFIGHTERS are battling a Northern California bushfire that’s threatening nearly 1,400 buildings, and they are hoping to take advantage of slightly cooler weather to tackle the flames — although wind and dry vegetation could still fuel the blaze.

Fire spokesman Israel Pinzon says that roughly 2,500 people had been forced from their homes.

Pinzon says officials lifted some mandatory evacuations on Tuesday night, though he didn’t know how many people were allowed to return home.

The fire has burned through about 334 square kilometres in rural areas northwest of Sacramento.

The fire is about 25 per cent contained with no structures yet damaged or destroyed.

The Northern California bushfire is just one of several massive fires burning in the Western United States and putting some Fourth of July plans on hold.

Officials have ordered more Utah residents to evacuate their homes as crews struggled to gain control over a bushfire burning near a popular fishing reservoir.

The fire has grown to 160 square kilometres over three days amid high wind gusts, steep terrain and extremely dry conditions.

It has destroyed about 30 structures and led officials to evacuate several hundred homes and cabins in the area about two hours southeast of Salt Lake City.

Officials on Wednesday didn’t have an updated count of buildings evacuated or destroyed. But they extended evacuations to an area dotted with trees and cabins stretching about 32 kilometres.

Officials believe ithe blaze was human-caused but are still investigating how it started.

A southern Colorado bushfire that has destroyed more than 100 homes is still growing.

Officials said on Wednesday that the fire has burned 381 square kilometres since it began on June 27.

Officials estimated that the fire about 330 kilometres southwest of Denver is still just 5 per cent contained.