Evaluation of Supercell Storm Triggering Factors Based on a CloudResolving Model Simulation

Autor(en)
Vlado Spiridonov, Mladjen Ćurić
Abstrakt

An attempt has been made in this study to examine the conditional instability parameters in the selected area and to determine themain ingredients responsible for initiation and evolution of supercell storm over Skopje, Macedonia on 6 August 2016. WRFmodel forecasts provide the basic meteorological parameters for cloud model initialization and the detail information aboutatmospheric instability potential as triggering factor for severe convection. The cloud model simulation has been performed withvery fine spatial and temporal resolution capable to resolve the detail aspects of convection. The results utilizing this novelmethod suggest that, upper level lifting, moisture advection, large CAPE, near surface convergence and increased potentialvortices in the selected area play substantial role in early assessment of the atmospheric status, convective instability and stormpotential. In addition the directional wind shear (veering) at the near surface layer, high storm helicity index, differential heatinginduced by the strong local forcing environment serve as triggering factors for initiation of supercell storm with rotationalupdrafts-mesocyclone. The cloud model simulation with fine resolution allows more detail insight into the storm dynamicsand the mechanism of generation of rotational updrafts and mesocyclone, a hook echo signature and the presence of boundedweak echo region as ingredients for supercellular structure and evolution. The overshooting top of 15 km, peak updraft speed of40 m/s, wind gust of 35 m/s and reflectivity which exceeds 70 dBZ indicates to the occurrence of a very severe storm. A longerlive cycle of storm and the intense water production, with extreme rainfall rate of 38 mm/5 min, contribute to formation ofexcessive torrential rainfall and local catastrophic flooding.

Organisation(en)
Institut für Meteorologie und Geophysik
Externe Organisation(en)
University of Belgrade
Journal
Asia-Pacific Journal of Atmospheric Sciences
Band
55
Seiten
439–458
Anzahl der Seiten
20
ISSN
1976-7633
DOI
https://doi.org/10.1007/s13143-018-0070-7
Publikationsdatum
02-2019
Peer-reviewed
Ja
ÖFOS 2012
105204 Klimatologie
Schlagwörter
ASJC Scopus Sachgebiete
Atmospheric Science
Link zum Portal
https://ucris.univie.ac.at/portal/de/publications/evaluation-of-supercell-storm-triggering-factors-based-on-a-cloudresolving-model-simulation(14ad9e80-6b32-4004-8565-823d576b88e7).html