Wildfire — S Sierra Foothills, California

2018-08-01 to 2018-08-18 · S Sierra Foothills, California

Event narrative

The Ferguson fire began on the Sierra National Forest just west of Yosemite, and spread to parts of the Stanislaus National Forest as well as into southern and western Yosemite National Park.

Wider weather episode

The Ferguson Fire started on July 13, 2018 at 2136 PDT in the South Fork Merced River drainage, 10 miles north of Mariposa, CA in Sierra National Forest. The cause of the fire is under investigation. The fire started in an area that has steep, rugged terrain with scarcely any road access and a heavy presence of beetle-killed trees. On the morning of July 14, a heavy equipment operator was killed in a bulldozer rollover accident while constructing line in a steep canyon. The fire grew rapidly under hot and dry weather conditions. Strong inversions each day resulted in smoke issues in the fire area that limited aircraft operations. Smoke impacts from the fire spread throughout Yosemite National Park, the Sierra Nevada and foothill and into the San Joaquin Valley. Highway 140 leading into Yosemite National Park was closed on July 14 and remained closed through August 14. Smoke impacts in Yosemite resulted in dangerous air quality causing Yosemite Valley and most of the eastern part of the park to be closed to visitors on July 25. This closure continued until August 14. Highway 41 leading into Yosemite from the south was also closed and did not reopen until August 24. Several communities just outside of Yosemite, including El Portal, Foresta, and the park employee housing at Rancheria Flat were subject to evacuations. From July 24 to 31, additional evacuations and repopulations of other areas continued to occur. On July 29, another tragic accident occurred when a tree fell, hitting and killing a firefighter. The weather moderated on August 6, which gave firefighters the opportunity to reinforce containment lines, mop up hot spots, and complete firing operations to keep the fire from spreading further into Yosemite National Park. The closure of Yosemite National Park for nearly three weeks had local and global impacts on those who had planned to travel to visit during that time. Economically, businesses were impacted in the gateway communities who depend on summer tourist season to sustain them through the year.

By August 18, the fire was contained and had burned 96,901 acres at a suppression cost of $117 Million. There were 19 injuries to firefighters and 10 structures destroyed.

Source: NOAA Storm Events Database, event_id 776253. Narrative written by the NWS forecast office that issued the report.