Thursday, 28 January 2021

Pretoria: The South African Weather Service has issued an updated weather forecast for South Africa. The SAWS said that during the past 48 hours, numerous severe weather-related impacts have been reported over the western parts of the Free State as well as over the north-eastern parts of the Northern Cape (covering the period 26 to 27 January 2021).

Some of these impacts included damage to (and closure of) roads, widespread flooding as well as evacuations of some communities and people stranded by rising floodwaters. It is likely that extensive damage to crops as well as waterlogged farmlands will ultimately lead to significantly impaired agricultural production in these areas.

Figure 1: A geostationary satellite image (Meteosat Second Generation) of Southern Africa at 08h00B on Thursday morning, 28 January 2021. Image courtesy EUMETSAT 2021.

The SA Weather Service forecast has been updated to take into account that the weather system that contributed towards the above mentioned impacts moved somewhat faster than the numeric models originally predicted.

A “Day Natural Colour” RGB satellite image for Southern Africa, valid for 08h00SAST 28 January 2021, can be seen in Figure 1, while a map indicating measured rainfall over the past 24 hours, 08h00 27 January to 08h00 28 January 2021 is shown in Figure 2. By comparison, Figure 3 indicates the model predicted rainfall which is likely to occur over South Africa between today and tomorrow.

Figure 2: A map of 24-hour rainfall measured between 08h00SAST 27 January to 08h00SAST 28 January 2021. Source: SA Weather Service.

 

Figure 3: Unified Model (UM) SA4 accumulated rainfall amounts (mm) from 28 until 29 January 2021. Source: SA Weather Service.

Therefore, the following warnings are valid for Thursday, 28 January 2021:

  1. Orange warning for disruptive rainfall is expected over southern and western Mpumalanga, Gauteng and the western Bushveld of Limpopo, as well as the north-eastern parts of the North-West Province, resulting in flooded low-lying areas, isolated incidents breaching of earth dam walls, general disruption to traffic and basic services, flooding of roads and settlements (both formal and informal), danger to life (particularly fast-flowing rivers and streams).
  2. Yellow warning for disruptive rainfall expected over the eastern and central parts of the Free State as well as over the eastern parts of the North-West Province, resulting in localised flooding as well as difficult driving conditions.

It is anticipated that the coming weekend will see a persistence of showers and thundershowers over the central parts of South Africa, whilst maximum temperatures should start recovering, heralding a spell of warmer, albeit humid weather in the days ahead. By contrast, the western interior should become sunny, dry and hot during the coming weekend.

The public are advised to monitor the SAWS Facebook page (@WeatherServic), Twitter @SAWeatherServic and the SAWS website (www.weathersa.co.za) for any significant changes in the weather forecast and updates to the warnings especially in the next week due to the high soil moisture content that can cause flooding with not much needed rain.