The Mesoscale Convective Systems with bow echo radar signatures as an example of extremely severe and widespread geohazard in Poland

Abstract

In the last two decades we can notice a significant increase of severe anemological events, which are mostly connected with mesoscale convective systems and a cold front of a deep low-pressure system. One of them are very strong winds with speeds more than 25 m/s. They caused material damage and threatening people's lives. The most dangerous are winds generated by mesoscale convective systems where radar reflectivity signatures of bow echo/derecho appeared. In this paper the area of occurrence of such phenomenon in Poland are described and the features of bow echo signatures on radar images are presented and explained. Additionally one of the most severe event and still very weakly known episode of 11 th August 2017 derecho in Poland is analysed. The damage data from European Severe Weather Database (ESWD) were analysed to confirm if the August 11th storm met derecho criteria. To identify the radar reflectivity signatures inside MCC the data from the Polish Institute of Meteorology and Water Management shared on the radar-opadow.pl site were used. The CAPPI 1 km data were very useful to determine the convective forms. After that the data from synoptic station were examined for presenting the running of selected meteorological elements. Finally, some information about material damage in infrastructures and forests are mentioned.

The impact of initial and boundary conditions on severe weather event simulations using a high-resolution WRF model. Case study of the derecho event in Poland on 11 August 2017

“…In this study, we present the effects of using varied initial conditions on simulations of severe weather events. Our analysis focused on a derecho event that occurred in Poland on 11 August 2017, one of the most intense and devastating events in recent years (Widawski, Pilorz 2018). We were looking for answers as to which initial conditions would predict this phenomenon as accurately as possible.…”

Diurnal and Seasonal Variability of ERA5 Convective Parameters in Relation to Lightning Flash Rates in Poland

“…Thunderstorms are most frequent during the summer (i.e., June-August) and over the southeastern part of the country (Bielec-Ba˛kowska 2003). The same period is also linked to the peak occurrence of severe weather outbreaks such as derechos and tornadic supercells that are responsible for considerable material losses in Poland (Celi ński-Mysław and Matuszko 2014; Pilorz 2015; Widawski and Pilorz 2018;Pilguj et al 2019; Pore R ba and Ustrnul 2020; Surowiecki and Taszarek 2020). A similar distribution of severe weather events can be observed based on the records from the European Severe Weather Database (ESWD; Dotzek et al 2009), which also indicate that the most common convective threat across central Europe is severe wind, followed by excessive rainfall, large hail, damaging lightning, and tornadoes (Groenemeijer et al 2017;Taszarek et al 2019).…”

A 10-Year Radar-Based Climatology of Mesoscale Convective System Archetypes and Derechos in Poland

“…Studies about MCS occurrence in Poland are uncommon. Prior research concerned mainly high-impact case studies (Walczakiewicz and Ostrowski 2010;Widawski and Pilorz 2018;Taszarek et al 2019;Poręba and Ustrnul 2020). A few collaborations focused on the occurrence of bow echos and derechos over the last few years (Celi nski-Mysław and Matuszko 2014;Celi nski-Mysław and Palarz 2017;Celi nski-Mysław et al 2019, 2020.…”