Powerful gusts of wind and dry conditions remain overriding concerns for Californian firefighters on Wednesday as they seek to tame a huge blaze that has destroyed hundreds of homes.

The so-called Thomas Fire has travelled 43 kilometres since it began on Dec. 4 to become the fifth largest wildfire in state history. It has charred more than 953 square kilometres of Ventura and Santa Barbara counties, an area larger than New York City.

A break in the hot, dry winds on Tuesday sapped the fire’s momentum and allowed crews to prevent further damage to homes.

But adverse weather will “promote significant fire growth (and) … hamper control efforts” on Wednesday, the California Department of Forestry and Fire Protection (Cal Fire) said in an evening advisory.

The fire, which was 25 per cent contained, will continue to threaten the coastal communities of Santa Barbara, Carpinteria, Summerland and Montecito as powerful Santa Ana wind gusts and humidity of less than 10 per cent will remain in the forecast until Friday, Cal Fire and the National Weather Service said.

Some of the 7,800 firefighters deployed against the blaze on Tuesday took advantage of the better weather to set controlled burns in a canyon near Carpinteria to deprive the flames of fuel, Cal Fire Captain Steve Concialdi.

Hundreds of homes destroyed

In Washington, where members of the House of Representatives met Vice-President Mike Pence to discuss the crisis, Rep. Julia Brownley said all resources had arrived to fight the blaze, which could take another week to contain. Her district includes Ventura.

USA CALIFORNIA WILDFIRES Firefighters extinguish Thomas Fire

Firefighters work to extinguish the Thomas Fire as it burns past a highway in Ventura, Calif., on Dec. 7. (Kyle Grillot/AFP/Getty Images)

The Thomas Fire has so far destroyed 701 homes and displaced more than 94,000 people. Efforts to combat the flames have cost more than $55 million US.

Many public schools in Santa Barbara and school districts nearby have cancelled classes this week and will not reopen until the annual winter break is completed in January.

Some of other fires burning over the past week in San Diego and Los Angeles counties have been largely brought under control.

The Los Angeles Fire Department said Tuesday that investigators had determined the Skirball Fire, which destroyed six homes in the city’s Bel-Air community, was started by a cooking fire at a homeless encampment underneath a freeway.