资源环境科技发展态势分析平台

On July 7th, 2017 numerous supercells affected the south - western part of Poland. Significant hail, severe wind gusts and one - tornado of estimated F2 intensity on the Fujita scale were reported. Thunderstorms developed in a warm sector within the low pressure trough. Moderate to high - shear and low to moderate buoyant environmental conditions led to rapid formation of supercells. The main aim of the study was to examine meteorological conditions which result in severe storms and to validate their projections in meteorological models.

Supercells were detected with the use of the Polish radar system "POLRAD" run by the Institute of Meteorology and Water Management - National Research Institute (IMGW). Additionally, geostationary and polar satellite data were used in the study. The data were provided by NOAA and METEOSAT. Surface and upper air meteorological conditions were obtained from hourly observations from synoptic stations in Poland and atmospheric soundings from Lindenberg, Prague, Wroclaw and Prostejov. High - resolution models AROME, COSMO and the mesoscale model ALARO were analysed. The examination of the radar and satellite data yielded an abundance of sharp and classic severe convection signatures as a bounded weak echo region (BWER), hook echo and radial velocity couplets. The most intensive supercells lasted > 2.5 h, with tops reaching 12 km, and reflectivity up to 67 dBz. Operational runs of ALARO, AROME and COSMO showed favourable for severe convection values of instability and wind shear. However, the models incorrectly simulated convection as multicellular and displaced it significantly.