Why this Tornado formed outside Johannesburg on Monday

Cold weather has gripped much of the country, but the dropping temperatures were not the only concern as a tornado touched down in the Magaliesberg, just outside of Johannesburg on Monday afternoon.

Mario Ferreira, a resident in Magaliesburg, posted a video of a tornado touching down in the remote area on Monday afternoon at approximately 15:30.

The video is just under a minute long, and Ferreira noted that the tornado touched down twice before he was able to begin recording.

What causes tornadoes?

Tornadoes form in unusually violent thunderstorms when there is sufficient (1) instability and (2) wind shear present in the lower atmosphere.

Instability refers to unusually warm and humid conditions in the lower atmosphere, and possibly cooler than usual conditions in the upper atmosphere.

Wind shear in this case refers to the wind direction changing, and the wind speed increasing, with height. An example would be a southerly wind of 15 mph at the surface, changing to a southwesterly or westerly wind of 50 mph at 5,000 feet altitude.

(click the image below to enlarge)

You can check out the footage of the Tornado below:

Another video taken by Amin Hassam, showed the tornado from his position on Koesterfontein Farm:

The extreme weather is expected to continue until Thursday, with an alert issued for severe thunderstorms with strong winds and heavy rains.

Possible large hail storms can also be expected over the central parts of the Free State, Gauteng as well as the central and eastern parts of the North West province, reports Weather24.

The South African Weather Service says disruptive snowfalls are expected over the south-western and western high grounds of KwaZulu-Natal, the northern high ground of Eastern Cape and the eastern and southern parts of the Free State.