A weak but potentially dangerous tornado swept across a farm in Heilbron, Free State, on Monday afternoon, as severe thunderstorms flared across the region.
The South African Weather Service (SAWS) confirmed that the tornado formed between 15:00 and 16:00 on 24 November 2025, after a line of storms “matured to be more severe in the afternoon”.
Forecaster Lehlohonolo Thobela said atmospheric conditions were primed for tornadic development.
“There were gusts around the region with identified shearing, convergence and moisture to form a convective cloud, which later resulted in a supercell. The conditions were favourable for a tornado to form,” Thobela explained.
SAWS noted that the tornado struck within a recognised climate hotspot for such events. The Free State, along with Gauteng, KwaZulu-Natal and Mpumalanga, historically records the highest frequency of tornadoes in South Africa.
Research also supports the seasonal timing. Long-term studies including work by the Water Research Commission show that tornado activity typically peaks between November and March.
“This supports the sense that warm moisture environments, combined with triggers from cooler systems, are key indicators of tornado formation during this period,” Thobela added.
Meteorologists said the setup closely resembled past severe weather outbreaks, including the 11 December 2017 Highveld supercell. Recent research into Highveld thunderstorms has found that most supercell storms occur in October and November, often lasting around an hour and covering distances of up to 50 kilometres. Terrain also plays a role in where the most severe storms develop.
Despite dramatic footage shared online, Monday’s tornado caused little to no damage.
“There were no further observed impacts or reports from the tornado, and it appears to have occurred in an open field,” Thobela said.
The tornado was rated an EF0 the weakest category on the Enhanced Fujita Scale with estimated wind speeds of 105 to 137 km/h. Such systems usually result in minor impacts, such as broken branches or light roof damage.
SAWS has cautioned residents that even weak tornadoes can be hazardous, especially for anyone caught outdoors as severe weather continues to affect large parts of the country.