Dry weather, high temperatures, and extremely low humidity brought conditions ripe for wildfire across southern Arizona in early June 2021. On June 10, the Moderate Resolution Imaging Spectroradiometer (MODIS) on board NASA’s Terra satellite acquired a true-color image of several large blazes in southeastern Arizona.
Each red “hot spot” marks an area where the thermal bands on the instrument detected high temperatures. When combined with typical smoke, as in this image, such hot spots are diagnostic for actively burning fire. A single large fire may have several hot spots, especially as fire is spreading in several directions or where the fuel at the center has been burnt, leaving fresh fuel (and active fire) only at the edges. Two major fires are seen in this image: the Telegraph Fire and the Mescal Fire.
The western fire is the Telegraph Fire, a fast-moving and dynamic fire that as of June 10 has burnt 84,860 acres of shrub and grass one mile southeast of Superior and one mile away from Top-of-the-World, Arizona. Evacuations have been ordered for parts of Top-of-the-World, Superior, Claypool, Miami, and Globe as firefighters focus on protecting lives, as well as public and private property. The fire ignited the afternoon of June 4 and is classified as human in origin. It is only 34 percent contained, with full containment date expected to be June 20. The exact cause is under investigation.
The Mescal Fire ignited on June 1 in the Mescal Mountains about 12 miles southeast of Globe and 7 miles northeast of Dripping Springs. As of the morning of June 10, it had burned 72,250 acres of desert brush, oak, and grasses. According to Inciweb Incident Information System, fire activity has reduced to moderate over the course of the last 24 hours as fire spread has reached most containment lines. The Mescal fire is considered 23 percent contained and is expected to reach 100 percent containment on June 30. At this time, several previously evacuated communities are being permitted to return home. However, temperatures are expected to range from the mid-90s to 101 degrees with 11-16 mph sustained winds. Combined with a relative humidity of only 3 percent, conditions continue to support a high potential for rapid return of active fire behavior. The start of the Mescal Fire is under investigation.