25 Sep 2023 | 11:33 AM UTC
South Africa, Lesotho: Adverse weather forecast to continue across much of both countries through at least Sept. 26 /update 1
Severe weather forecast across South Africa and Lesotho through Sept. 26. Weather-related disruptions ongoing in Western Cape Province.
Event
Severe weather is forecast to continue across much of South Africa and Lesotho through at least Sept. 26. Weather-related disruptions, including flooding, road closures, and power outages, are ongoing in parts of Western Cape Province as of Sept. 25 as stormy conditions impact the region.
The South African Weather Service (SAWS) has issued an updated media release warning that a strong cut-off low pressure system will continue to bring dangerous weather conditions across much of the country Sept. 25-26. Heavy rainfall, thunderstorms, strong winds, and rough seas are likely to continue over Western and Eastern Cape provinces through Sept. 26, with rainfall totals of 10-20 cm (4-8 inches) and winds gusting up to 80 kph (50 mph) possible. Strong winds are also expected over the country's interior, enhancing the risk of wildfires spreading in parts of the country. Thunderstorms are possible in northeastern regions.
As of Sept. 25, the SAWS has issued the following weather warnings across the country:
Orange level 9 (out of 10) disruptive rain warnings: parts of west-central and western Eastern Cape and southern Western Cape provinces.
Orange level 6 disruptive rain warnings: Across much of the rest of central Eastern Cape Province.
Orange level 6 damaging wind warnings: Across southern coastal areas and adjacent inland areas of Eastern and Western Cape provinces.
Orange level 6 damaging wave warnings: Along much of the southwestern and parts of the south-central coastline.
Yellow level 4 disruptive rain warnings: Across central Western Cape Province.
Yellow level 2 disruptive rain, thunderstorms, and damaging winds warnings: Across parts of the rest of central, north-central, southern, and western South Africa.
Yellow level 2 damaging wave warnings: Along much of the southeastern and parts of the south-central coastline.
The Lesotho Meteorological Service has forecast isolated showers and storms across Lesotho Sept. 25-26, as well as possible snowfall in elevated parts of the country.
Authorities will likely issue new alerts or update/rescind existing advisories as weather conditions change over the coming days.
Heavy rainfall and strong winds are causing disruptions across parts of Western Cape, including Cape Town, as of Sept. 25. Reports indicate several homes have been flooded in Durbanville, Bo-Kaap, Schaapkraal, Bellville South, Belhar, Sandvlei Macassar, Strand, Gordon's Bay, and Knorhoek. Properties have also been damaged by strong winds in Cape Town's CBD and Hout's Bay. Weather-related power outages have been reported in many areas, including Philippi, Gugulethu, Eastridge, Steenberg, Wetton, Bellville, Plattekloof, Green Point, and Pinati Estate. Several roads in Cape Town and surrounding areas have been closed due to flooding, as have sections of the N1 and N2 highways, including the N2 near Botrivier where floodwaters have washed away a bridge.
Further sustained heavy rainfall could trigger additional flooding in low-lying communities near rivers, streams, and creeks. Urban flooding is also possible in developed areas with easily overwhelmed stormwater drainage systems. Sites located downstream from large reservoirs or rivers may be subject to flash flooding after relatively short periods of intense rainfall. Landslides are possible in hilly areas, especially where the soil has become saturated by heavy rainfall.
Authorities could issue mandatory evacuation orders for flood-prone communities over the coming days. Disruptions to electricity and telecommunications services are possible where significant flooding or landslides impact utility networks.
Precipitation could fall as snow in the higher elevations over the coming days. Wind gusts could cause blowing and drifting snow; decreased visibility is likely in mountainous areas.
Floodwaters and debris flows may render some bridges, rail networks, or roadways impassable, impacting overland travel in and around affected areas. Ponding on road surfaces could cause hazardous driving conditions on regional highways. Authorities could temporarily close some low-lying routes that become inundated by floodwaters.
Severe weather could also trigger flight delays and cancellations at airports across the affected area. Authorities may temporarily suspend port operations along the southwestern and southern coastlines if strong winds trigger hazardous sea conditions, impacting freight and passenger maritime traffic. Flooding could block regional rail lines; freight and passenger train delays and cancellations are likely in areas that see heavy rainfall and potential track inundation.
Localized business disruptions may occur in low-lying areas; some businesses might not operate at full capacity because of flood damage to facilities, possible evacuations, and some employees' inability to reach work sites.
Advice
Monitor local media for weather updates and related advisories. Confirm all transport reservations and business appointments before travel. Make allowances for localized travel delays and potential supply chain disruptions where flooding has been forecast. Do not drive on flooded roads. Charge battery-powered devices in the case of prolonged electricity outages.
