Through a partnership between NASA and NOAA, this field campaign will demonstrate the first-of-its-kind hyperspectral microwave airborne measurements (CoSMIR-H) and will be complemented by other passive (infrared, visible) and active (lidar) sensors onboard the NASA ER-2 aircraft. Serving as a future NASA planetary boundary-layer (PBL) mission prototype, WH2yMSIE aims to capture a wide variety of thermodynamic, moisture, and PBL regimes across a variety of surface types. The ER-2 will be flying over a variety of land and ocean environments.