Large wildfires developed across Northern California at the end of July during a period of high temperatures, low humidity and unusually dry fuels. A powerful fire whirl developed with the Carr Fire, creating significant wind damage to western Redding and rapid fire growth. The Mendicino Complex became the largest wildfire in California history. A state of emergency was declared at state and federal levels due to the fires.

High Wind in NORTHERN SACRAMENTO VALLEY, CALIFORNIA
From 26-JUL-18 19:30:00 to 26-JUL-18 20:00:00 (PST-8)
Magnitude: 134.00 EG
Reported by: NWS Storm Survey

A powerful fire whirl developed within the Carr Fire in western Redding, CA on July 26th, with winds estimated in excess of 143 mph, equivalent to an EF3 tornado. The fire whirl was estimated to be on ground from 7:30���8:00 p.m. The fire whirl caused extensive tornado-like damage while rapidly spreading the fire. The winds crumpled high tension electrical transmission towers, damaged homes, and debarked and uprooted trees. Wind damaged areas included locations untouched by fire, and included signs of ground scouring. The damage path was 2 miles long, with an estimated width of about half a mile. Three people were killed inside their Redding home after the structure's walls were blown out and the roof collapsed on the occupants. Several other homes suffered significant roof damage. A firefighter was killed while driving his vehicle near the fire whirl. Three bulldozers were impacted by flying debris, rocks, embers, smoke and intense heat, with the operators suffering injuries including burns and cuts from broken glass.

Wildfire in MOUNTAINS SOUTHWEST SHASTA COUNTY TO NORTHERN LAKE COUNTY, CALIFORNIA
From 27-JUL-18 12:15:00 to 31-JUL-18 23:59:00 (PST-8)
Property damage: 56.00M
Reported by: Fire Department/Rescue

The Mendocino Complex Fire (made up of the River and Ranch Fires) spread across Colusa County, Glenn County, Lake County, and Mendocino County, becoming the largest wildfire in California history at 459,123 acres. The Mendocino Complex Fire was not contained until September 18. There were 157 residential buildings destroyed, 123 others destroyed. In addition, there were 13 residential buildings and 24 other buildings damaged. The fires caused at least $56 million in insured property damage. The city of Lakeport, communities of Kelseyville, Lucerne, Upper Lake, Nice, Saratoga Springs, Witter Springs, Potter Valley, and Finley, parts of Hopland, and the tribal communities of Hopland Rancheria and Big Valley Rancheria were evacuated. There was 1 firefighter killed (on August 13), 4 firefighters were injured.

Wildfire in NORTHERN SACRAMENTO VALLEY, CALIFORNIA
From 23-JUL-18 15:00:00 to 31-JUL-18 23:59:00 (PST-8)
Property damage: 1.50B
Reported by: Fire Department/Rescue

The Carr Fire began on the afternoon of July 23, 2018, at the intersection of Highway 299 and Carr Powerhouse Road, near French Gulch in Shasta County. The fire is reported to have been started accidentally by a vehicle towing a trailer that had a tire blow out, causing the steel rim to scrape along the pavement, generating sparks that ignited dry vegetation along the edge of the highway. Local winds generated by the fire are reported to have caused the fire to spread quickly.
At the end of July, the fire was the sixth most destructive fire in California history at 112,888 acres, with 1,378 structures destroyed, 965 of them homes. The fire was not fully contained until August 30, reaching 229,651 acres in size with a total of 1,079 residences, 22 commercial structures, 503 outbuildings destroyed. There were also 190 residences, 26 commercial structures, and 61 outbuildings damaged. About 38,000 people were evacuated from their homes. There were a total of 8 deaths from the fire, 3 of them firefighters. A large fire whirl in Redding has been reported as being responsible for 4 of the deaths, and this has been listed as a separate event. Damage costs to insured buildings are estimated at $1.5 billion for the Carr Fire.