Development changes were mapped for two points in time (2001 and 2012), and for two adjacent counties in Texas, Bastrop and Travis counties. These two counties are at high risk of wildfire, and expanding development is increasing vulnerability. Lateral development was organized into five categories: infill, radial, isolated, clustered, and linear. Wildfire risk was modeled using the RANDIG software package. Simulations were run on 39 weather scenarios, and two landscapes. Two-way ANOVA’s and post hoc analysis were used to measure variation in Burn Probability and Conditional Flame Length for each category of development. Burn Probability maps were validated against historic large fires.