A New Approach for the Analysis of Deep Convective Events: Thunderstorm Intensity Index

Abstract

In this study, an investigation of a new thunderstorm intensity index (TSII) derived from lightning data is performed, along with its relationship to rain, wind, hail and waterspouts as well as instability indices (CAPE, LI, KI, and DLS). The study area is located in the northeastern Adriatic and includes various terrain types in a relatively small area (coastal, flatlands, hills and valleys, and mountain regions). The investigated period covers 11 years (2008–2018). The mathematical algorithm standing behind the TSII is based on the well-established methodology of lightning jump, allowing us to recognize areas where intensification in thunderstorms occurred. Our results suggest that these areas (with a positive TSII) experience significantly higher rain intensities and have higher total amounts of precipitation compared with areas where thunderstorms did not generate a TSII. Moreover, 76% of thunderstorm hail cases were associated with the presence of a TSII within a 15 km distance. The maximum reported wind speed also has higher values on a day with a TSII. Out of 27 waterspout events associated with lightning, 77% were related to a TSII. Due to the good spatial (3 km × 3 km) and high temporal (2 min) resolution of lightning data, the TSII can recognize even a local and short-lived intense system that is often misread by radars and satellites due to their inferior temporal resolution. The TSII is designed to be used as a climatological and diagnostic variable that could serve in lieu of more established data sources (e.g., station measurements and observations, radar imagery, etc.) if they are unavailable.

Simulating Hail and Lightning over the Alpine Adriatic Region - A model Intercomparison Study

“…Further, to assess the ability of LPI to reproduce the observed lightning activity, lightning data from the Lightning Detection Network (LINET) (Betz et al, 2009) (Franc et al, 2016), showing significant improvement in the sensitivity detection toward smaller stroke current amplitudes. For most of the European region (Franc et al, 2016;Jelić et al, 2021), the average minimum detectable signal is 0.7 kA, and the median location accuracy error is ±84 m. Here, we considered total lightning information, i.e., we did not differentiate between types or polarities of lightning flashes as LPI presents the overall potential for lightning activity without preferences to the type or polarity of lightning discharges. The total lightning for the examined cases was taken from the 2D database of lightning flashes at a 3 km x 3 km horizontal and 2 min temporal resolution (developed by Jelić et al, 2021) over the domain shown in Figure 1a.…”

Simulating Hail and Lightning Over the Alpine Adriatic Region—A Model Intercomparison Study

“…With continuous improvements of the LINET network, the median values of detected current amplitude values had decreased by half from 2009 (Franc et al., 2016), showing significant improvement in the sensitivity detection toward smaller stroke current amplitudes. For most of the European region (Franc et al., 2016; Jelić et al., 2021), the average minimum detectable signal is 0.7 kA, and the median location accuracy error is ±84 m. Here, we considered total lightning information, that is, we did not differentiate between types or polarities of lightning flashes as LPI presents the overall potential for lightning activity without preferences to the type or polarity of lightning discharges. The total lightning for the examined cases was taken from the 2D database of lightning flashes at a 3 km × 3 km horizontal and 2 min temporal resolution (developed by Jelić et al., 2021) over the domain shown in Figure 1a.…”

Spatiotemporal Variability of Convective Events in Romania Based on METAR Data

“…The main objective of this study is to evaluate the convective episodes based on METAR and SPECI data collected from 17 Romanian airports from 2012 to 2022. Extensive Although convective events have a great spatiotemporal variability, climatological studies can provide valuable information in respect to their spatial and temporal differences in a particular region, as well as providing trends on various time-scales [34,35]. Based on climatological scientific results, the user can anticipate important changes in local or regional weather, as well as severe weather associated with convection events [29].…”