Spatiotemporal distribution of strong convective cells over northern Serbia, 2008–2010

Abstract

Abstract Knowledge of the spatial distribution of severe convective cells (SCCs) can determine the areas with the most frequent occurrence of these events, and helps in the protection of the most vulnerable areas. An objective analysis of a three year observation of strong convective cells (CCs) in northern Serbia is presented, based on data collected via meteorological radar. The CC and SCCs are defined by radar reflectivity thresholds of 45 and 55 dBZ, respectively, and are analysed at constant altitude plan position indicator (CAPPI) levels of 4.0 km (CAPPI4) and 5.5 km (CAPPI5). The analysis showed that the dominant occurrence of thunderstorm cells was directed from southwest to northeast. The spatial distribution from year to year was variable; however, the analysis identified areas with frequent thunderstorm cells. The number of grid points where CCs occur is smaller at the CAPPI5 than at the CAPPI4. There is a more frequent occurrence of CCs than SCCs: there were no CCs in only 0.58% of grid points during the entire three year period at the CAPPI4, while for SCCs it was 39.82%. This difference was even greater at the CAPPI5: 1.42% for CCs and 55.47% for SCCs. At most of the grid points (67–79% at the CAPPI4 and 78–88% at the CAPPI5, depending on the year), no SCCs were observed for any given year.

Keywords

• frequency of thunderstorm cells
• hail
• radar reflectivity
• severe convective cell