Photo thanks to a google images search
Irvine Ranch Conservancy and the Orange County Fire Authority have a volunteer program called Fire Watch. It's a neighborhood watch program, where during high fire risk conditions, volunteers are called upon to go out and monitor habitat for signs of fire so that the situation can be stopped before it gets out of control. At the Fire Watch website link above, you can sign up to be a fire watch volunteer.
Another way to help on a more personal level is to be mindful of the dangers you pose to the environment on a high risk day. For example, (an a huge personal pet peeve of mine) throwing your cigarette butt out of your car window. Not only is it illegal (littering), but discarded cigarettes and matches can also could land in the dry roadside brush and during windy conditions, it could spark a fire.