Amid strong, erratic winds, the Lava Fire burning near Weed grew explosively on Monday, and evacuations were ordered by the Siskiyou County sheriff.
A second set of evacuations was ordered Tuesday for a smaller fire nearby.
The Lava Fire, which was started by lightning on Friday morning in the Shasta-Trinity National Forest, had burned about 500 acres on Sunday evening. By Monday morning, it was 1,446 acres (2.2 square miles), and by Monday night it was 13,300 acres (20 square miles) and had crossed Highway 97. The fire was 20% contained at that point.