|CZU Lightning Complex fires|
|Location||San Mateo and Santa Cruz counties, California|
|Total area||86,509 acres (35,009 ha)|
The CZU Lightning Complex fires were wildfires that burned in Northern California starting in August 2020. The fire complex consisted of fires in San Mateo and Santa Cruz counties, including fires that had previously been separately tracked as the Warnella and Waddell fires. The firefighting effort was primarily administered by the California Department of Forestry and Fire Protection (Cal Fire).
The fires started at 6:41 AM on August 16, 2020, the result of a thunderstorm that produced close to 11,000 bolts of lightning and started hundreds of fires throughout California. These lightning strikes initially started fires separately known as the Warnella Fire, near Davenport and the Waddell Fire, near Waddell Creek, as well as three fires on what would become the northern edge of the CZU Complex fire. Two days after the fires began, a change in wind conditions caused these three northern fires to rapidly expand and merge, growing quickly to over 40,000 acres.
The fires destroyed 1,490 buildings, including in the communities of Boulder Creek, Bonny Doon, Swanton, and along Empire Grade Road. Fires burned in both Butano and Big Basin Redwoods state parks, where a number of historic buildings were destroyed, including the visitor's center at Big Basin.
On September 22, Cal Fire reported that the complex, which had covered 86,509 acres (35,009 ha), had been fully contained On December 23 Cal Fire announced that the fire was controlled, stating that the fire was fully extinguished and has no risk of reignition. However, it was later discovered that the fire was not quite completely extinguished; redwoods continued to smolder well into 2021. 
The documentary The CZU Fire In Their Own Words – Fighting Fires, Losing Homes, and Rebuilding Community covers the fires and was created and directed by Boulder Creek resident Peter Gelblum .
- 2020 California wildfires
- August 2020 California lightning wildfires
- "CZU Lightning Complex (Including Warnella Fire)". Cal Fire Incidents. California Department of Forestry and Fire Protection. October 27, 2020. Retrieved September 22, 2020.
- Lakshmi, Sarah; Pickoff-White, Lisa; Green, Matthew; Rodriguez, Joe Fitzgerald (August 22, 2020). "Trump Approves 'Major Disaster' Declaration in CA as Fires Break State History Records". KQED. Retrieved August 22, 2020.
- "12,000 lightning strikes sparked over 560 fires across California". KTVU FOX 2. August 20, 2020.
- "CZU Lightning Complex Fire Progression". Youtube. CAL FIRE CZU San Mateo-Santa Cruz. Retrieved 26 September 2020.
- Andre, Drew (August 26, 2020). "Boulder Creek neighborhood destroyed in CZU lightning Complex". Retrieved September 10, 2020.
- Martinez, Lauren (August 30, 2020). "CZU Lightning Complex fires: Neighbors helping each other out after devastating wildfire in Bonny Doon". Retrieved September 10, 2020.
- Larson, Amy (August 28, 2020). "CZU fire destroys trains at Swanton Pacific Ranch near Davenport". KRON 4. Retrieved September 10, 2020.
- Green, Jason; Kelliher, Fiona; Webek, Evan (August 20, 2020). "Bay Area Fire Updates: 4 dead, 400,000 acres burned, thousands of structures destroyed with fires out of control". The Mercury News. Retrieved September 13, 2020.
- Williams, Michael (August 28, 2020). "Fallen trees, crumbling roads and a suspected pipe bomb: CZU crews battling hidden dangers". San Francisco Chronicle. Retrieved September 13, 2020.
- Graff, Amy (August 20, 2020). "Fire wipes out Big Basin State Park's historic buildings". San Francisco Chronicle. Retrieved August 22, 2020.
- @CALFIRECZU (December 28, 2020). "The #CZULightningComplex has been controlled. myemail.constantcontact.com/CZU-Lightning-Complex-Controlled.html?soid=1133733276209&aid=CaUIaABQooE" (Tweet) – via Twitter.
- Harrell, Ashley (4 March 2021). "More than six months after the fire started, Big Basin is still burning". SFGate. Retrieved 2 July 2021.
- Brooks, Eric. "PHOTOS: Smoldering tree found at California's Big Basin months after destructive wildfire". Microsoft News, citing CAL FIRE of 30 June 2021. Retrieved 2 July 2021.
- Vainshtein, Annie (August 20, 2020). "LNU? SCU? CZU? How the Lightning Complex and other California fires get their names". San Francisco Chronicle. Retrieved August 22, 2020.
- Fuller, Thomas; Bogel-Burroughs, Nicholas (2020-08-31). "A Vow of Silence, a Cabin in the Woods, a Terrible Wildfire". The New York Times. ISSN 0362-4331. Retrieved 2020-12-05.
- Walker, Wilson (August 24, 2020). "CZU Lighting Complex: Fire Victim Died Trying To Flee Flames, 6 Rescued; Weather Helps Firefighters". CBS-5 KPIX News. Retrieved August 29, 2020.
- "CZU Lightning Complex (Including Warnella Fire)". Cal Fire Incidents. California Department of Forestry and Fire Protection.
- "CZU Lightning Complex". InciWeb. National Wildfire Coordinating Group.
- CZU Lightning Complex damage assessment maps, by county