This project will make use of new weather radar technology to assess the role that small-scale droplets and ice crystals in clouds have on the development of lightning. Phased-array radar is a next-generation technology for weather radar that can provide extremely fast scanning of clouds and precipitation. The fast-scanning ability is key for detecting key lightning processes that happen on the order of seconds. The potential societal impact of this project would be the downstream improvement in lightning prediction, a significant public safety problem. The project also includes plans for recruiting a diverse cohort of students to participate in the deployment and data analysis, thereby ensuring training of the next generation of scientists.<br/><br/>This study will use new phased array radar technology to provide dual-polarization observations of thunderstorms at very short time scales to study the storm electrification process. High temporal resolution and full instantaneous vertical data are critical to characterizing the structures which promote lightning initiations near storm updrafts, describing the interplay of lightning channels with microphysical features such as ice crystal alignment signatures, and exploring the direct scattering of radar signals from channels within radar-sampled volumes. The S-band Horus radar and the C-band PAIR radar will be deployed alongside the RaXPol X-band radar within reach of the Oklahoma Lightning Mapping Array (LMA) network in 10 deployments across 2023 and 2024. The researchers will conduct a scan sequence repeating every 80 s, including storm-scale dual-Doppler scans over the full storm volume, to resolve updrafts and downdrafts, while interleaving essentially continuous updates at lightning and eddy time scales to provide fast-time and detailed spatial resolution within mesoscale context. The team will also separate hydrometeors within resolution volumes using Doppler spectral polarimetry methods to study microphysical properties.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.