June of 1990 will long be remembered as one of the hottest months in Arizona history. The temperature rose to 122 F (50C) in Phoenix and to 106 F (4 1 C) in Payson on June 26. These temperatures established a new daily record at Phoenix's Sky Harbor Airport, and equaled the June record temperature in Payson. Along with the record heat, an extended period of drought persisted. These conditions combined to produce critically high fire danger throughout Arizona, and especially in the Mogollon Rim country and the Tonto National Forest north of Payson, AZ.
[This publication is referenced in the "Synthesis of knowledge of extreme fire behavior: volume I for fire managers" (Werth et al 2011).]