Lightning and Severe Weather: Process in the context of satellite applications “Measurements from the vantage point of space to: Investigate the formation and intensification of severe storms that lead to the formation of tornados; and Assess if satellite-based products, coupled with advanced algorithms and models, can result in more accurate forecasts and warnings. “ “The primary objective of this meeting is to clearly define the scientific questions of a future field campaign and to determine the observations necessary to answer them” Framework 1.What do we know now? (energetics, trends, physics, process, relation to satellite observables) 2.What do we need to know (questions, objectives) 3.What parameters/measurements do we need to satisfy science objectives? (satellite, airborne, ground….)

Overarching Objectives and Related Science Questions Using combined satellite, airborne, and ground-based measurement platforms relate lightning characteristics (e.g., flash rates, lightning jumps”[LJ]/dives [LD], dimension, radiances and energetics) to the: a) Occurrence or non-occurrence of severe weather (Tornado, hail, wind); To what degree can lightning character in combination with or without satellite imager data be used to detect and delineate severe weather types (hail, tornado, wind etc.)? How do we optimally combine lightning, ABI, ground and/or model data to improve a physically-based severe weather detection algorithm? Can downscaling of satellite-based lightning measurements improve severe weather detection algorithms and discernment of processes in the vertical profile? Can lightning data be used to identify and mitigate for potential OT-based false alarms? What do “null” cases tell us about the limitations of lightning application; e.g., decoupling of physical processes?

Overarching Objectives and Related Science Questions (cont) b) Structure of and changes in severe storm kinematic, microphysical, and electric charge properties and processes What are the physical coupling(s) between lightning characteristics (LJ/LD intensity, flash size/area/radiance, IC:CG, polarity) up/downdraft properties(volume, mass flux etc.) microphysical processes, mesocyclone character, storm top divergence/rotation, and low- level outflow? How do storm physical properties and tendencies in lightning flash co-vary in time/space with the evolution and character of OTs or other satellite observables? Does the lag between convective initiation and first lightning relate to the probability of severe weather? How does severe storm 3-D charge structure control lightning propagation, how is this manifested in satellite observations, and how is this related to severe storm evolution, lifecycle and intensity? How do lightning optical characteristics and their evolution relate to storm microphysical profile, lifecycle and properties of OTs? What environmental parameters (e.g., thermodynamics, shear, aerosols etc.) control lightning behavior and how are they related to severe storm physical properties?

Physical Parameters/Measurement Multi-spectral visible/IR cloud-top radiances (TB) Total lightning 2-D and 3-D (time/space resolved, IC/CG; e.g., optical/VHF/VLF –LF source/event to stroke scales) from space and ground Cloud top and ground-based lightning optical radiance/E-Field; high speed camera? Cloud and precipitation hydrometeor profiles of liquid/mixed/frozen water content, size distribution, number concentration, type, charge, and vertical profile [in situ, remote] Cloud top liquid/ice hydrometeor properties (contents, sizes, numbers, type) Storm 4-D winds (u, v, w, t), thermodynamic and bulk charge structure (extending from inflow through cloud top) Tropospheric/lower stratospheric environment (thermodynamics, wind, aerosol properties) Coupled modeling (with electrification and sat. sim) for further parameter interpretation; data assimilation for improved nowcast/forecast.