On September 10, 2020, the August Complex set a record for the single-largest wildfire in the modern history of California, reaching a total area burned of 471,185 acres (1,907 km2).

[6] The three major Bay Area fires, the SCU, LNU, and the CZU Lightning Complex, collectively burned about 846,000 acres (3,420 km2) by mid-September 2020, destroyed 2,723 structures, and took 6 lives.

Later that day, the Fire Weather Watch was upgraded to a Red Flag Warning,[12] noting the risk of abundant lightning already apparent as the storms moved toward the region from the south.

[13] These colliding weather systems then created excessive atmospheric instability that generated massive thunderstorms throughout much of Northern and Central California.

Such thunderstorms are rare for California, but were more typical of Midwest garden-variety storms, with one location near Travis Air Force Base going from around 80 °F (27 °C) to 100 °F (38 °C) in nearly 1–2 hours.

[14] Additionally, much of these storms were only accompanied with dry lightning and produced little to no rain, making conditions very favorable for wildfires to spark and spread rapidly.

These lightning strikes sparked up to 585 wildfires, many of which grew to be very large at a rapid pace due to parched brush, especially in Northern California.

[48] By August 20, the fire burned 140,000 acres (570 km2) and was 5% contained, evacuating people in the East San Jose foothills,[50] and threatening the Lick Observatory with flames.