Nature Unleashed as the Western and Eastern Cape Experience Severe Winter Weather

We saw eight weather warnings in place recently as a second, and stronger, cold front moved over the south-western Cape in quick succession, bringing damaging winds and disruptive rain. Vox Weather Meteorologist Michelle du Plessis shares a short overview.

(Cover image courtesy of SABC News: Facebook)

Two consecutive cold fronts moved across the south-western parts of South Africa this week (10 to 15 May), bringing widespread heavy rain, damaging winds and major disruptions across parts of the Western Cape.

The first cold front moved through on Sunday the 10th of May, followed by a second and stronger system on Monday the 11th. This second front brought the most intense weather, with heavy rainfall continuing into Tuesday the 12th across several areas.

Widespread Flooding and Disruptions

Rainfall totals were particularly significant across the western and south-western parts of the province. Several public reports indicate very high accumulations, including around 213 mm near Piketberg by Tuesday morning, with rain still continuing at the time of the report.

In the Koue Bokkeveld, between Ceres and the Cederberg, some areas reportedly received up to around 280 mm, with ongoing rain, road closures, power outages, limited internet access and cellphone tower disruptions being reported.

Some areas may even have received more than 300 mm, particularly some of the mountainous regions.

These very high totals led to widespread flooding and disruptions, with several schools in the Western Cape closed on Tuesday due to the severe weather conditions.

Damaging Winds

The heavy rain was not the only major concern. Damaging winds were also a significant component of this system.

Official 24-hour wind gust observations for Tuesday showed gusts of 117 km/h at Beaufort West and Ladismith, 113 km/h at Ngqura, 109 km/h at Cape Point, 100 km/h at Sutherland, 98 km/h at Dohne, 94 km/h at Hermanus, 93 km/h at Laingsburg, and 91 km/h at both Cape Town AWS and Uitenhage.

Some private weather station reports indicated even stronger gusts, including a reported maximum wind gust of 142 km/h near Piketberg.

These strong winds contributed to widespread damage, including power outages, fallen trees, infrastructure damage and transport disruptions. The closure of the N1 towards Cape Town near Worcester was particularly significant, as it affected a major transport route into the city and likely disrupted the movement of goods and services. A number of flights from the Cape Town and George airports were also affected.

Nature Unleashed

This event highlights the tremendous potential impact of winter cold fronts when multiple systems move through in quick succession. The combination of saturated ground, persistent rainfall, strong winds and rough conditions can quickly lead to flooding, infrastructure damage, travel delays and power supply challenges.

Although strong cold fronts are a normal part of the Western Cape winter rainfall season, this event was particularly significant because of the intensity of the second front, the high rainfall totals over a short period, and the widespread damaging winds.

Conditions are expected to improve from Wednesday as the second cold front moves away from the province. The latest forecast currently indicates dry conditions across most regions of the Western Cape for the rest of the week.

How SA’s winter weather patterns compare to our neighbours

South Africa is one of the few countries in southern Africa that regularly has snow  – in places – in winter.

Vox Weather Meteorologist Michelle du Plessis tells us more.

South Africa’s climatic diversity is largely due to its geographic position at the southernmost tip of Africa, where it’s influenced by both the warm Agulhas Current on the east coast and the cold Benguela Current on the west coast. Its varied topography – ranging from high plateaus to mountain ranges like the Drakensberg – creates conditions cold enough for snowfall in winter. Being the furthest south on the continent, South Africa is also directly affected by mid-latitude cyclones and cut-off low-pressure systems. When looking at our neighbouring countries, clear contrasts emerge in winter weather patterns.

(Image left courtesy Mantle Plumes; Image right courtesy Vox Weather)

Lesotho, though an independent country, is entirely landlocked within South Africa.

Its high elevation – most of the country lies above 1,800 metres – means it experiences regular snowfall in winter, particularly over the Maloti Mountains, much like surrounding high-lying areas of South Africa.

(Photo courtesy Snow Report SA / Marietjie Hayward)

Namibia and Botswana experience dry, sunny winters with cool nights and warm days, but their generally low elevation and arid conditions make snowfall virtually impossible.

In Namibia, bergwinds or “oosweer” often bring warm, dry weather and occasional sandstorms as strong north-easterly winds prevail after the passage of cold fronts. Although rare, light snowfall can occur in the far south of Namibia when a particularly strong cold front moves unusually far north.

Zimbabwe and Mozambique have subtropical to tropical climates. Their winters are dry and mild, with average temperatures rarely dropping low enough to produce frost, let alone snow.

Eswatini experiences slightly cooler conditions in winter, especially in its highland areas, but snowfall is extremely rare due to its lower elevation and more humid climate.

(Map image courtesy of BBC News)

These regional differences highlight how South Africa’s southern location, combined with its topographical range and oceanic influences, makes it uniquely positioned to experience a wide variety of winter weather, including rain and snow – conditions seldom seen in its neighbouring countries.

(Click here to find out how snow weather occurs.)

The Effect of Climate Change on South Africa’s Winter Weather Patterns

What is happening to SA’s winters and is climate change playing a significant role? Vox Meteorologist Michelle du Plessis tells us more.

Data shows that winter temperatures across southern Africa have been steadily rising since the 1960s, with fewer days of frost and freezing conditions.

According to the NOAA, extreme cold events are now far less common – and when they do happen, they’re generally milder than in the past.

In the Western Cape, where winter rainfall is vital, climate models show that the rainy season is becoming shorter and more variable.

While some winters still bring strong cold fronts and good rainfall, others are marked by long dry spells.

The WMO warns that drought risks are increasing, especially in Mediterranean-type climates like the south-western Cape.

Interestingly, while total rainfall may decrease, when storms do occur, they may be more intense – bringing short bursts of heavy rain rather than steady soaking periods. This is because warmer air holds more moisture, which can lead to more powerful frontal systems when they develop.

Recent studies suggest that mid-latitude frontal systems – the cold fronts that bring winter rain – may grow stronger under climate change. However, this doesn’t mean we’ll get more of them. Instead, we may see fewer, but more intense, winter storms, followed by longer dry periods in between.

What this means for South Africa

In short, South African winters are becoming:

  • Warmer, with fewer frost days;
  • More variable, with rain falling in short, intense bursts; and
  • Less predictable, meaning long-range planning is harder.

A Note on Snow Forecasting at Vox Weather

Some early snow forecasts recently circulated on social media suggested possible snowfall over parts of Gauteng, North West, the Highveld, and other areas that rarely experience snow during late July. At Vox Weather, we chose not to post about these projections – and here’s why.

Advanced snow forecasts, particularly more than five days ahead, are often subject to significant change. In fact, updated model guidance today NO LONGER indicates snowfall over these north-eastern regions at all.

Our approach as meteorologists to snow forecasting involves more than just looking at model snowfall outputs.

We analyse:

  • The SYNOPTIC SYSTEM expected (e.g. a cold front or cut-off low);
  • The availability and timing of PRECIPITATION; and
  • The FREEZING LEVELS (the altitude at which temperatures are cold enough for snow to form and reach the ground).

These factors must all align for snowfall to be possible. A shift in any of them can lead to significant changes in where snow may fall – or if it occurs at all.

As of the latest forecast, we see:

  • A cold front expected to move in on Friday 25 July.
  • A strong ridging high-pressure system to follow, introducing colder air over southern South Africa during the weekend of 26 and 27 July.
  • Forecast snowfall now largely restricted to the Eastern Cape, Lesotho, the southern Free State, and adjacent high-lying areas.

At Vox Weather, we prefer to wait until we see consistency in multiple forecast runs – usually within a five-day window – before communicating potential snowfall.

 

This ensures that our updates are as accurate and reliable as possible.