Synoptic conditions of the derecho storm. Case study of the derecho event over Poland on August 11, 2017

This study presents a comprehensive synoptic analysis of one of the most violent storms recorded in recent years in the north-western part of Poland, which occurred on August 11, 2017. Its development took place ahead of a waving cold front in the tropical air mass, downstream of the upper-level trough. The thunderstorms formed over Lower Silesia in the afternoon and moved towards Gdańsk Pomerania to occur over the B altic Sea after midnight on August 12, 2017, where they gradually disappeared. As the thunderstorms moved through this area, they ranged from single convective cells and unorganized multicell storms through supercell thunderstorms to mesoscale convective systems in the form of bow echo squall lines and the mesoscale convective vortex (MCV). The convective system, evolving over time, fulfilled the derecho criteria. Its development was related to the presence of both the upper and mid-level jet stream, which supported the formation of a strong rear inflow jet (RIJ) in the rear part of the convective system, being one of the main factors generating the formation of a bow echo squall line with strong wind gusts. The maximum wind gusts recorded on August 11, 2017, are among the highest in the history of Polish measurements and amounted to 42 m/s in Elbląg, 36 m/s in Chrząstów, 35 m/s in Gniezno, and around 30 m/s at several other stations.

[1]  P. Struzik,et al.  Monitoring the 11 August 2017 storm in central Poland with satellite data and products , 2021, Meteorology Hydrology and Water Management.

[2]  M. Wdowikowski,et al.  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 , 2021, Meteorology Hydrology and Water Management.

[3]  Alexey P. Bykov,et al.  Diagnosis and modelling of two destructive derecho events in European Russia in the summer of 2010 , 2021, Atmospheric Research.

[4]  Mateusz Taszarek,et al.  A 10-Year Radar-Based Climatology of Mesoscale Convective System Archetypes and Derechos in Poland , 2020, Monthly Weather Review.

[5]  D. Schultz,et al.  An 18-year climatology of derechos in Germany , 2019, Natural Hazards and Earth System Sciences.

[6]  Marek Półrolniczak,et al.  Derecho Evolving from a Mesocyclone—A Study of 11 August 2017 Severe Weather Outbreak in Poland: Event Analysis and High-Resolution Simulation , 2019, Monthly Weather Review.

[7]  J. Pinto,et al.  Synoptic-scale conditions and convection-resolving hindcast experiments of a cold-season derecho on 3 January 2014 in western Europe , 2019, Natural Hazards and Earth System Sciences.

[8]  Daniel Celiński-Mysław,et al.  Kinematic and thermodynamic conditions related to convective systems with a bow echo in Poland , 2018, Theoretical and Applied Climatology.

[9]  Daniel Celiński-Mysław,et al.  The occurrence of convective systems with a bow echo in warm season in Poland , 2017 .

[10]  C. Crossett.  An Examination of the Dynamics of a Rear-Inflow Jet Associated with an Idealized Mesoscale Convective System , 2016 .

[11]  B. Czernecki,et al.  A Cloud-to-Ground Lightning Climatology for Poland , 2015 .

[12]  Dorota Matuszko,et al.  An analysis of selected cases of derecho in Poland , 2014 .

[13]  T. T. Fujita,et al.  Manual of downburst identification for Project NIMROD , 2013 .

[14]  Karimzadeh Hamid,et al.  Investigation of the passage of a derecho in Belgium , 2012 .

[15]  C. Gatzen,et al.  Two cold-season derechoes in Europe , 2011 .

[16]  G. Bryan,et al.  A Multimodel Assessment of RKW Theory’s Relevance to Squall-Line Characteristics , 2006 .

[17]  R. Johns,et al.  Synoptic and Mesoscale Analysis of a High-Latitude Derecho Severe Thunderstorm Outbreak in Finland on 5 July 2002 , 2006 .

[18]  B. Stevens.  ATMOSPHERIC MOIST CONVECTION , 2005 .

[19]  David J. Stensrud,et al.  An Observational Study of Derecho-Producing Convective Systems , 2004 .

[20]  Stephen F. Corfidi,et al.  Cold Pools and MCS Propagation: Forecasting the Motion of Downwind-Developing MCSs , 2003 .

[21]  Zuzanna Bielec-Bąkowska.  Long-term variability of thunderstorm occurrence in Poland in the 20th century , 2003 .

[22]  J. Scott Greene,et al.  A NEW SPATIAL SYNOPTIC CLASSIFICATION: APPLICATION TO AIR-MASS ANALYSIS , 1996 .

[23]  M. Weisman.  The Genesis of Severe, Long-Lived Bow Echoes , 1993 .

[24]  M. Kurz.  Synoptic diagnosis of frontogenetic and cyclogenetic processes , 1992 .

[25]  R. Rotunno,et al.  A Theory for Strong, Long-Lived Squall Lines , 1988 .

[26]  Robert H. Johns,et al.  Derechos: Widespread Convectively Induced Windstorms , 1987 .

[27]  Joseph B. Klemp,et al.  The Dependence of Numerically Simulated Convective Storms on Vertical Wind Shear and Buoyancy , 1982 .

[28]  Tünde Lemler,et al.  A case study of a derecho storm in dry, high-shear environment , 2021 .

[29]  Lucas Wexler,et al.  Glossary Of Meteorology , 2016 .

[30]  Harold E. Brooks,et al.  16.3 BASELINE CLIMATOLOGY OF SOUNDING DERIVED PARAMETERS ASSOCIATED WITH DEEP, MOIST CONVECTION , 2002 .