Understanding and predicting the dynamic behavior of our planet's environment over multiple spatial and temporal scales remains an outstanding scientific challenge , . More than 50 years of investment and advancements in remote weather-sensing systems (satellite-based as well as ground-based radar) have resulted in remarkable capabilities; however, these systems cannot deliver observations to meet current requirements for timeliness, positional precision, and the acquisition of data that can only be obtained in situ. Highly mobile observations systems are needed to deliver in situ data that are critical for the verification and validation of current models and simulations. This is the challenge in engineering the tools of scientific discovery, one of the 14 Engineering Grand Challenges of the 21st Century posed by the National Academy of Engineering . This article addresses specific challenges in designing and deploying unmanned aircraft systems (UASs) for sampling severe local storms.