Cold front in SA: Why it snows and how it happens

A young boy is seen playing with snow at a Park in Thokoza, Ekurhuleni, east of Johannesburg. Picture: Ntombi Nkosi/IOL

A young boy is seen playing with snow at a Park in Thokoza, Ekurhuleni, east of Johannesburg. Picture: Ntombi Nkosi/IOL

Published Jul 10, 2023


In an extraordinary turn of events, residents across Gauteng and the South African highveld awoke to a mesmerising sight - snow falling gently descending from the heavens, transforming the landscape.

The South African Weather Service (Saws), in response to this unexpected phenomenon, has released weather alerts cautioning the public about the potential disruptions that could arise from the inclement weather.

Snowfall in Gauteng is an extraordinary occurrence, as the region is known for its mild winters and predominantly dry climate. The South African Weather Service explained that a unique combination of weather patterns created this rare spectacle.

Meteorologists attribute snowfall in Gauteng to a convergence of cold air masses from the south and east with a low-pressure system moving across the region. These weather systems clashed, resulting in ideal conditions for snow formation.

The freezing temperatures accompanied by moisture-laden air led to the creation of intricate ice crystals, which then fell as snowflakes onto the ground, transforming parts of Gauteng into a magical winter realm.

Snow is formed when tiny ice crystals in clouds stick together to form snowflakes. Ice crystals grow around dirt or particles in the atmosphere. Snowflakes fall to the ground when they become heavy enough.

Children attempt to build a snow man at a suburb in Johannesburg. Picture: Timothy Bernard/African News Agency (ANA)

Temperature and moisture in the air affect the shape and size of snowflakes. Snowflakes that fall through cold, dry air produce powdery snow that sticks together.

Snowflakes are formed when ice crystals come into contact with each other and form symmetrical patterns.

If conditions closer to the ground are not negative, falling snow may turn into sleet.

Sleet is a type of winter precipitation that consists of small ice pellets formed by freezing raindrops or melted snowflakes. It can also refer to a mixture of rain and snow or hail. This may occur when a warm layer of air lies above a below-freezing layer of air at the Earth’s surface.

The impact of this unexpected snowfall has been significant. Mountain passes have been rendered treacherous due to icy conditions, prompting authorities to temporarily close several routes as a precautionary measure.

Communities nestled in higher elevations have been temporarily isolated, as access roads have become impassable. Livestock farmers are on the lookout for possible losses, as unexpected snow and icy conditions pose challenges to their animals' well-being.

The South African Weather Service continues to closely monitor the situation, providing timely updates and guidance to mitigate any potential risks arising from disruptive weather.

Despite the logistical challenges and temporary inconveniences, many Gauteng residents have embraced the rare snowfall, eagerly venturing outdoors to experience this extraordinary event.

The last significant snowfall in Gauteng occurred over a decade ago, making this recent event even more remarkable.

As Gauteng continues to adapt to the unexpected winter onslaught, authorities urge residents to exercise caution, remain informed through official weather channels, and extend support to one another during this exceptional time.