The fire was started by lightning strikes east of
Loyalton along the eastern edge of the
Sierra Valley, near Mount Ina Coolbrith on the
Tahoe National Forest. A fire lookout on Smith Peak in the
Plumas National Forest first reported smoke from the burgeoning fire to the Plumas dispatch center in
Quincy at 4:27 p.m. PDT on Friday, August 14. Limited road access prevented ground crews from getting near the fire for several hours. Despite the efforts of helicopters and air tankers, by 7:28 p.m. the fire had burned . By the morning of August 16, the fire had expanded to . Evacuation orders were issued for areas in Lassen County south of
SR 70 and west of
US 395. SR 70 was closed between
SR 49 and US 395 as fire crews worked to prevent the fire from spreading north of
Beckwourth Pass. The fire briefly jumped north of SR 70 and east of US 395 but was quickly stopped in those directions. By the evening of August 16, helped by strong winds, the fire had burned . Evacuation orders were expanded to Balls Canyon Road, Long Valley Road,
Bordertown, Copperfield, and
Cold Springs as the fire spread east into Nevada and the
Humboldt-Toiyabe National Forest. About 580 firefighters, 42 engines and 6 aircraft were on the scene. Crews had made progress on the southeast flank of the fire on August 17, mandatory evacuations were lifted for Cold Springs, and SR 70 was reopened. The Dog Valley and Long Valley areas of the Carson Ranger District on the Humboldt-Toiyabe National Forest were closed to recreational access. By evening, advisory evacuation orders were in place for Loyalton,
Chilcoot,
Vinton, and
Sierra Brooks. Lightning strikes started several new fires to the south around 7:30 pm, but rain after midnight helped slow fire activity. As of August 17, five homes and six other structures had been destroyed. On August 18, the fire had been largely contained in the north and east, and mandatory evacuations were lifted in Lassen County. However, it continued spreading rapidly to the south and west, largely due to the lightning strikes there the previous day. The fire grew to and was 10 percent contained. High winds continued throughout August 19, but crews had managed to slow the fire spread considerably. Evacuation advisories were lifted for Cold Springs and Bordertown. By the evening, evacuation advisories were also lifted for Chilcoot, Vinton and Loyalton, although evacuation orders remained in place for Balls Canyon Road, Long Valley Road, and Copperfield, and an evacuation advisory for Sierra Brooks. On the morning of August 20, evacuation advisories were lifted for Sierra Brooks and Copperfield. As of 5:44 pm on August 20, the fire had burned and was 60 percent contained. Air quality continued to be extremely poor in Sierra Valley and Reno, with visibility highly impaired by smoke. On the morning of August 21, evacuation orders remained in place for Balls Canyon Road and Long Valley Road. The fire had burned and remained at 60 percent containment. At 6:30 am on August 22, the fire was at and was 75 percent contained. Wind activity decreased significantly over the weekend helping fire crews to expand containment. A total of six homes and 29 other structures were reported destroyed. All evacuation orders were lifted as of this time, though the Dog Valley area of the Humboldt-Toiyabe National Forest remained closed. The fire was declared 100 percent contained on August 26. It burned in total. == Effects ==