Resolving Convective‐Scale Cloud and Precipitation Structures in Tropical Cyclone Rainbands With Novel Raman Lidar Observations

Abstract Low‐level clouds in the tropical cyclone (TC) rainbands modulate the radial inflow of warm, moist boundary layer air, which can impact TC intensity. Yet, precisely measuring rainband cloud boundaries with existing remote sensing techniques remains a challenge. To address this observational gap, this work leverages compact Raman lidar (CRL) backscattered power data collected by a NOAA P‐3 aircraft to distinguish between low‐level convective clouds, shallow clouds, stratiform precipitation, and clear air in the TC rainbands. CRL data are analyzed together with traditional tail Doppler radar (TDR) and in situ observations. An empirical CRL classification scheme finds that convective cloud, stratiform rainfall, and clear air sectors have unique kinematic and precipitation properties. A case study of Hurricane Sam (2021) demonstrates how this method resolves cloud structures with enhanced horizontal detail compared to the TDR. For the first time, the horizontal scales of low‐level convection and shallow clouds are determined. Environmental shear‐relative analyses reveal that the downshear‐left quadrant contains the most low‐level convective coverage and the least clear air. Meanwhile, the upshear‐right quadrant has little low‐level convection and plentiful clear air. Increasing environmental shear from low to moderate magnitudes amplifies these TC shear‐induced precipitation asymmetries. A conceptual framework is developed to highlight the unique information provided by the CRL when classifying cloud and precipitation structures.