The Relationship Between Penetrating Tops in a Tornadic Supercell and the Evolution of the Storm at Mid and Low Levels: Analysis of Both Geosynchronous Satellite and Ground-based, Mobile, Rapid-scan, Polarimetric, X-band, Doppler Radar Data
Abstract
There has been much speculation about how penetrating tops and collapsing tops might be related to tornadogenesis in supercells. Possible relationships are important both for predictive/diagnostic purposes and for basic scientific reasons. For example, do penetrating tops belie strong updrafts in the storm and low-level convergence near the surface, which could intensify existing vorticity and advect it upward? Do collapsing updrafts induce downdrafts, which produce surface convergence and which can also intensify existing vorticity? Can signatures at cloud top detected in satellite imagery be used for short-term forecasts?
On 14 May 2018 the evolution of a multicell storm into a supercell, which produced a tornado and large hail in south-central Kansas, was documented by RaXPol, a mobile, Rapid-scan, X-band, Polarimetric, Doppler radar, over a three-hour period. GOES-16 1-minute visible (0.64 micron) and IR (10.3 micron) data are used to track the locations and maximum heights of penetrating tops. The pixel resolution at the satellite subpoint is 500 m in the visible and 2 km in the IR; the resolution is slightly less at the latitude of Kansas. The spatial resolution of RaXPol at 10 km range is 175 m; the update time for full 360 deg scans is 20 s. In this study we explore the temporal and spatial relationships between the penetrating tops and the development of a low-level hook echo, weak-echo regions (WERs), bounded weak-echo regions (BWERs), mesocyclones, and polarimetric signatures such as the ZDR arc, ZDR column, etc. This study is significant in that it makes use of both high-resolution, rapid-scan mobile radar data and high-resolution, "rapid-scan" satellite data.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.A32C..08B
- Keywords:
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- 3310 Clouds and cloud feedbacks;
- ATMOSPHERIC PROCESSESDE: 3314 Convective processes;
- ATMOSPHERIC PROCESSESDE: 3329 Mesoscale meteorology;
- ATMOSPHERIC PROCESSESDE: 3354 Precipitation;
- ATMOSPHERIC PROCESSES