Intercomparison Between Polarimetric Radar, GOES-16 Satellite, and Lightning Indicators of Storm Severity in Supercells

Observational nowcasting of supercell evolution mainly has focused on the use of radar data, particularly in the WSR-88D dual-polarization era. However, the successful implementation of GOES-16 and its accompanied high spatial and temporal resolution data have introduced new possibilities for accurate real-time assessment of severe weather potential in supercells. In this study, comparisons are made between derived products from radar and satellite data that act as indicators of storm severity and proxies for storm updraft strength in several supercell cases. The data that are analyzed include satellite products developed to detect attributes of overshooting tops (OTs), and a polarimetric radar algorithm used to determine the heights of columns of enhanced differential radar reflectivity factor (Z_DR). Also, depending on availability, lightning data (flash extent, flash energy, flash size) from the GOES-16 Geostationary Lightning Mapper also are compared with remote sensing data. These products all can be used to infer changes in storm severity and previously have been shown to be diagnostic or prognostic indicators of severe weather.

The goal of this study is to establish direct relationships between available satellite, polarimetric radar, and lightning products that are all thought to be indicators or predictors of severe weather. Of particular interest is (i) how and when the combined suite of products provide complementary information vs. when a particular product alone provides unique indicators of impending severe weather and (ii) how indicators of storm severity change leading up to important storm processes, including tornado formation. Previous work by the first and second authors on this topic used data from GOES-14, but the focus for this talk will be on GOES-16 supercell data from 2017 onward.