South Africans are being urged to keep an eye on the latest weather warnings this weekend as a cut-off low moves eastwards across the country, bringing the risk of thunderstorms, flooding, strong winds and very cold conditions.
The South African Weather Service (SAWS) has escalated its severe weather warnings, with an Orange Level 5 warning in place for parts of the Northern Cape on Friday.
A broader Yellow Level 4 warning for severe thunderstorms covers parts of the Northern Cape, Free State, North West and southern KwaZulu-Natal.
The most serious storms could bring heavy downpours, large hail, damaging winds, excessive lightning and localised flooding of roads, settlements and bridges.
But the weather system is not expected to stay in one place.
SAWS says the cut-off low will move eastwards over the weekend, bringing scattered to widespread showers and thundershowers, windy conditions and falling temperatures to parts of the Free State, Gauteng, the Eastern Cape, KwaZulu-Natal and eastern North West.
There is also a risk of severe thunderstorms developing over parts of the Free State, North West and Gauteng from Friday afternoon into Saturday evening.
By Sunday, the focus of the severe thunderstorm risk is expected to shift further east towards Mpumalanga and KwaZulu-Natal, with the possibility of the storms extending into southern Limpopo.
Johannesburg: rugby fans should watch the skies
The unsettled conditions will coincide with one of the biggest sporting events of the weekend.
The Springboks face the All Blacks at FNB Stadium in Johannesburg on Saturday, with kick-off at 5.10pm.
Johannesburg is expected to be cool with variable cloud and the possibility of afternoon thundershowers on Saturday.
That means supporters travelling to Soweto should be prepared for rapidly changing conditions, particularly during the build-up to the match.
The weather has already affected preparations for the fixture.
Airlink has withdrawn its planned formation flypast over FNB Stadium, citing an unfavourable weather forecast. The decision also comes as the South African Civil Aviation Authority reviews the airline's controversial low-level flypast over Cape Town's DHL Stadium last weekend.
The possibility of thunderstorms also means fans should take care when travelling to and from the stadium, particularly if heavy rain develops.
KwaZulu-Natal faces a rough weekend
KwaZulu-Natal is among the areas expected to see increasingly unsettled conditions as the system moves east.
SAWS has warned of severe thunderstorms in parts of the province, with the potential for heavy rain, damaging winds, hail, excessive lightning and localised flooding.
Strong winds are another concern, with the weather service warning that they could damage temporary structures, bring down trees and create dangerous conditions for motorists.
Along the coast, rough seas and strong winds could create additional hazards.
Motorists should be particularly cautious on roads affected by standing water and should never attempt to cross a flooded road or bridge.
Eastern Cape could turn very cold
The Eastern Cape is also expected to experience a significant change in conditions.
The movement of the cut-off low is expected to bring cold, wet and windy weather to parts of the province, while very cold conditions are possible over high-lying areas.
Snow is possible over some higher ground as temperatures fall.
The combination of cold, rain and wind could be particularly difficult for vulnerable people and livestock.
Don't be caught out by the spring sunshine
The weather system is a reminder that the arrival of spring does not mean the end of dangerous winter-style weather.
Temperatures can change quickly when a cut-off low moves across the country, while thunderstorms can develop rapidly and produce intense rainfall over relatively small areas.
For motorists, the biggest risks are sudden downpours, poor visibility, flooded roads, hail, strong winds and lightning.
SAWS is advising the public to continue monitoring its forecasts and warnings because the exact location and intensity of severe thunderstorms will depend on how the weather system develops.
People in affected areas should avoid crossing flooded roads, bridges and streams, secure loose objects that could be blown around and avoid seeking shelter under isolated trees or near metal structures during thunderstorms.
Anyone heading to outdoor events this weekend should also check the latest forecast before leaving home.
For rugby fans heading to FNB Stadium, that advice is particularly relevant: the match may be the big event of Saturday, but the weather could be an important part of the journey there and home again.