Assessing Cloud-Top Brightness Temperature and Cloud Types to Identify the Precursors to Thundersnow Development

Determining when a lightning strike might occur in a winter storm can be difficult due to the complex microphysical processes and mesoscale interactions that drive the development of snowfall. Next-generation satellite instruments such as the Geostationary Lightning Mapper and the Advanced Baseline Imager on the Geostationary Operational Environmental Satellite R (GOES-R) Series, however, have new capabilities to detect lightning and microphysical characteristics of clouds. Following previous research by Harkema et al. 2019, into the relationship between next-generation satellite data and thundersnow, this project investigates the cloud top characteristics in relation to the development of lightning by combining GLM data with the Night-time Microphysics and Day Cloud Phase Distinction imagery. When assessing the 10.3 brightness temperature leading up to lightning during an April 2018 snowfall case and categorizing the cloud types (e.g., low, middle, high, water, mixed, or ice) within the area, it is expected that cloud top cooling, or a decrease in brightness temperature, acts as a precursor to lightning development. Previous research has demonstrated that thundersnow events produce higher snowfall accumulations and that more research is needed to understand the microphysical processes that lead up to lightning in a winter storm. With information on the precursors to lightning, operational forecasters will have additional tools to help anticipate winter storm lightning development, the potential for higher snowfall accumulations, and associated hazards.