With 2,520 fires burning of land, the 2020 wildfire season was the largest wildfire season in the US state of Arizona since 2011. Wildfires occur year-round in the state but are most numerous and typically burn the largest swaths of land during spring and summer. Peak fire season in the Southwest typically runs from May, when conditions are windy, hot, and dry, through mid-July, when the North American Monsoon provides the region with precipitation to slow fire activity.
By the end of the year, more than fifty fires larger than had burned within the state. However, the most notable fire of the season, the Ocotillo Fire, burned only over four days and threatened the town of Cave Creek. It destroyed 20 buildings, including 8 homes.
Historically, while "fire season" in Arizona began in April in desert areas and May around the Mogollon Rim with peak activities near July, there is now a fire risk year-round. Arizona is drought prone, with precipitation much different between the deserts and mountains. When the snow pack on the mountain melts, the moisture can reduce the risk of wildfire events. However, climate change can raise the snow line, reduce snow pack, decrease runoff, or cause earlier snowmelt. A risk of decreasing precipitation and dry monsoons could heighten fire risks. Heavy rainfall can allow vegetation to grow, and many of these plants quickly dry out in just hours.
In April, the Arizona Department of Forestry and Fire Management expected a "potentially active" fire season reminiscent of the 2019 season. Increased grass load from a wet winter is expected to contribute to an elevated risk of fire in the Central Arizona deserts. Southwest Coordination Center Predictive Services forecasted an Above Normal risk for significant wildland fires from May through July for most of Arizona (excepting the Colorado Plateau), with fire potential returning to Normal by August with the arrival of a climatologically average monsoon. They cited above normal fine fuel loading in southern Arizona deserts and an active weather pattern through mid-June to support this risk. A fire department helicopter crashed while bringing supplies to firefighters, killing the pilot.
The following is a list of fires that burned more than , or produced significant structural damage or casualties.