This loop of GOES-10 3.9 micrometer shortwave InfraRed (IR) imagery shows several "hot spots" (black to red enhancement - red pixels have an effective brightness temperature of 37 C / 100F or greater) from fires burning across parts of Montana and North Dakota during the late evening / early morning on 31 October / 01 November 1999. The largest fire started in the vicinity of Sidney, Montana (station identifier KSDY), and spread southeastward into the Little Missouri National Grassland in North Dakota. Over 100,000 acres was burned by this fire.

Hourly surface reports are plotted on each image. Strong winds associated with a cold frontal passage played a major role in the initiation (power line arcing) and rapid propagation of these fires during the night. The leading edge of the cooler air behind the front (lighter gray enhancement) can be seen advancing southeastward across Montana into the Dakotas and Wyoming.