NCAR staff at the Mesa Laboratory on the afternoon of 29 October 2003 had a panoramic view of smoke plumes from a wildfire burning in the foothills 10 miles northwest of Boulder, Colorado. The Overland fire started early Wednesday morning, possibly because of a downed power line. Fanned by gusty, erratic winds, the fire spread rapidly, with flames reaching 100 feet high in some places. By that evening, the blaze covered 4,000 to 5,000 acres. Forest fires are exceedingly complex phenomena. They possess complex chemistry, exhibit nonlinear behaviour, and their associated radiation and combustion properties are not well understood. The mechanisms by which they spread are also not well understood, but have to do with the advection of hot gases and lofting of burning material. A better understanding of wildfires could lead to an ability to predict, manage, and train for such disasters. Scientists at NCAR have coupled numerical regional weather simulations with fire-spread models and created visualizations that advance the understanding of wildfires. SCD supports and manages high-performance computers used by researchers to run their models, as well as visual supercomputers dedicated to visualizing these data.