Extreme weather conditions create challenges for the welfare of pigs during commercial transport. The thermal environment within a commercial swine trailer has been shown to vary from heat stress to cold stress within the same trailer on the same trip, and dead and down pigs have been identified as an unacceptable source of losses for the industry. The overall goal of this project is to provide science-based recommendations for bedding, boarding and misting practices during pig transport in order to improve animal thermal conditions and trailer air quality. To achieve this overall goal, the approach of this research focused on understanding the micro-environment experienced by pigs on a trailer during transport for mild and extreme weather. The instrumentation system has been developed for quantifying thermal micro-environment in a commercial swine trailer during transport.