overnight, fire crews focused their efforts on two large brush fires, threatening los angeles coty. >> reporter: in the hills outside los angeles, a fire fight in a heat wave. extreme conditions, fire explosive. nearly 800 homes have been evacuated. >> i was just sobbing, like didn't want to lose everything. >> this inferno refused to lay down. threatening neighborhoods. >> i'm really feeling kind of scared, because i've had to leave my home and i don't know what's going to happen. >> reporter: the air attack here is critical. they're using helicopters to reach hillsides and firefighters on the ground, but resources are spread thin. those helicopters are going from fire to fire. across the west, some 8,000 firefighters are on the frontlines of 20 huge wildfires. a searing heat wave, facing fire and heat, this fierce summer battle is just beginning to explode. >>> the orlando nightclub shooter bought plane tickets to travel to california on a flight just two days after the shooting, federal officials tell nbc news. it was apparently to visit his ailing mother-in-law. the tickets were p