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All organisms have some range of temperature that constrains their ability to function properly (i.e., thermal sensitivity) and can even influence individual fitness. Thus, understanding the relationship between organisms and their thermal environments is fundamental to their conservation and management. Little is known about the thermal environments of sagebrush (Artemisia spp.) communities and the effects of fire on the thermal landscape. Our objective was to provide a baseline of spatial and temporal thermal heterogeneity by measuring operative temperature within a sagebrush landscape affected by fire. Operative temperature characterizes the temperature of organisms in their environment independently of thermoregulation by integrating ambient temperature, solar radiation and conductive and convective heat transfer between organisms and their environments. Sagebrush communities affected by fire provided many thermal options for organisms. We observed a wide thermal gradient with a range of operative temperature from -8� to 61� C. Furthermore, when ambient temperature was 10� C, operative temperature varied 37� C (range: -3� to 34� C). Fire increased thermal heterogeneity across the landscape. Unburned sagebrush areas were cooler and had a lower rate of increase than burned sagebrush areas indicating that this relationship was magnified as ambient temperature increased. Additionally, the magnitude at which thermal environments were modified differed among unburned and burned, big (A. tridentata spp.) and low sagebrush (A. arbuscula) areas. Unburned big sagebrush areas buffered operative temperature relative to ambient temperature slightly more than burned big sagebrush, unburned low sagebrush, and burned low sagebrush areas. These results show high thermal variation among sagebrush communities and that fire alters thermal patterns across the landscape, which will likely influence the behavior of sagebrush obligate organisms, including Greater Sage-grouse (Centrocercus urophasianus).