Livestock are produced in a variety of environments, some of which present considerable thermal challenges to productive performance and even survival. Biometeorology plays a key role in rational environmental management of agricultural animals, under either current climate variability or with possible global change scenarios. This review presents assessments of those impacts on animal agriculture (primarily in terms of performance [e.g., feed intake/efficiency and subsequent growth; milk production], but including effects on mortality) resulting from extreme events. Several scenarios of global change, as well as climatological data, have been used in developing the analyses presented, and results from the various analyses are compared. The focus is primarily on warm/hot weather, with heat waves and global warming used as specific examples for developing risk management considerations. Discussion of the results is included from the perspectives of current and historical weather variability, as well as potential future weather.