Articles | Volume 2, issue 2
https://doi.org/10.5194/wcd-2-373-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wcd-2-373-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Apr 2021
Research article |
| 28 Apr 2021
| 28 Apr 2021
A dynamic and thermodynamic analysis of the 11 December 2017 tornadic supercell in the Highveld of South Africa
Lesetja E. Lekoloane
CORRESPONDING AUTHOR
South African Weather Service, Pretoria, 0001, South Africa
Global Change Institute, University of the Witwatersrand, Johannesburg, 2050, South Africa
Mary-Jane M. Bopape
South African Weather Service, Pretoria, 0001, South Africa
Tshifhiwa Gift Rambuwani
South African Weather Service, Pretoria, 0001, South Africa
Thando Ndarana
Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria, 0001, South Africa
Stephanie Landman
South African Weather Service, Pretoria, 0001, South Africa
Puseletso Mofokeng
South African Weather Service, Pretoria, 0001, South Africa
School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Johannesburg, 2050, South Africa
Morne Gijben
South African Weather Service, Pretoria, 0001, South Africa
Ngwako Mohale
South African Weather Service, Pretoria, 0001, South Africa
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This study considered the upper dynamics associated with the South Atlantic Ocean high pressure system that extends across the South African domain. This extension of this system occurs in two ways. The dynamics are studied by considering the evolution of energy and it is shown that the upper level processes are different between the two types of the extension. The weather systems that occur in the upper develop very differently and have different implications for rainfall over South Africa.
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This study considered the upper dynamics associated with the South Atlantic Ocean high pressure system that extends across the South African domain. This extension of this system occurs in two ways. The dynamics are studied by considering the evolution of energy and it is shown that the upper level processes are different between the two types of the extension. The weather systems that occur in the upper develop very differently and have different implications for rainfall over South Africa.
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Short summary
We analysed a tornadic supercell that tracked through the northern Highveld region of South Africa for 7 h. We found that atmospheric conditions were conducive for tornado-associated severe storms over the region. A 4.4 km resolution model run by the South African Weather Service was able to predict this supercell, including its timing. However, it underestimated its severity due to underestimations of other important factors necessary for real-world development of these kinds of storms.
We analysed a tornadic supercell that tracked through the northern Highveld region of South...
