This report documents the analysis of data collected through the Long-Term Pavement Performance program to characterize the impact of environmental factors on pavement performance. The objectives of this analysis were to identify and quantify the effects of environmental factors and pavement design on pavement performance in the absence of heavy loads; develop recommendations for mitigating these effects through effective design, materials selection, and construction; estimate the portion of pavement damage caused by environmental factors; and establish a database of pavement design features, materials properties, and performance to be used in the future for similar analyses.