A team of 188 Australians and New Zealanders are heading to northern California, Oregon and Washington to help tackle the fires that have so far killed six people, destroyed 500 homes and burnt more than 375,000 hectares.
The contingent includes nearly 60 New South Wales firefighters and 12 from Queensland, among representatives from other states.
Deputy Commissioner of the New South Wales Rural Fire Service, Rob Rogers, says Australian firefighters are in a unique position to help.