More widespread rain and thundershowers are expected over the summer rainfall region during the next few days.
The area of normal to above-normal rainfall for this time of the year should include the entire maize-production region. It will be cloudy to overcast during the weekend with widespread precipitation over the central to north eastern parts.
The following is a summary of weather conditions during the next few days:
• General:
o Most of the country will receive rain during the next few days.
o Rainfall should be normal to above normal over the important grain-production areas. o The winter rainfall region will also receive normal to above-normal rainfall.
o Temperatures will be near normal over most of the interior, but somewhat above normal over the western parts on average.
o Strong south easterlies are possible over the southwestern parts, especially by Saturday (22nd) and Sunday (23rd).
• Rainfall:
o While rain will focus on the central areas at first, most of the rainfall should shift north eastwards during the weekend, with some significant falls indicated in certain areas according to current forecasts.
o Scattered thundershowers will initially occur over the central to western parts of the country (mostly central to eastern Northern Cape, western to southern North West, the Free State and onto the Eastern Highveld) until Friday (21st).
o Widespread rain and thundershowers are possible over the central to north eastern parts on Saturday (22nd). Significant 24-hour totals are possible over the eastern parts of North West, Gauteng, northern Free State, western Mpumalanga and southwestern Limpopo according to current forecasts. It will be cloudy over large parts in the northeast.
o Scattered rain and thundershowers are possible over the central to north eastern parts on Sunday (23rd) when it will also be overcast, windy and cooler in the east/northeast. Significant 24-hour totals are possible over western Limpopo and surrounding areas according to current forecasts.
o Apart from light showers in the northeast, accompanying cloudy and mild conditions, little to no rain is expected over the interior on Monday (24th) and Tuesday (25th).
o It will become cloudy with scattered showers and thundershowers over the far western interior by late Tuesday (25th) according to current forecasts, spreading into the central interior by Wednesday (26th).
• Temperatures:
o It will be much cooler over the eastern to north eastern parts from Saturday (22nd) / Sunday (23rd) compared to the preceding days. Especially maximum temperatures will be significantly lower. Lower maximum temperatures will occur in conjunction with extensive cloud cover the eastern to nort heastern parts until Monday.
o Minimum temperatures over the Eastern Highveld will be in the single digits (below 10°C) by early next week. o It will be hot to very hot over the western interior and West Coast on Sunday (23rd) and early next week according to current forecasts, spreading to the Karoo on Wednesday (26th).
Overview of expected conditions over South Africa during the next few days
The interaction of an upper-air trough over the southwestern parts, a tropical low to the north together with a strong high-pressure system to the south will once again result in very favourable conditions for normal to above-normal rainfall over most of the summer rainfall region. The position of the systems will result in especially widespread precipitation during the weekend over the central to north eastern parts. By next week, another upper-air system may develop in the west and may result in scattered rain and thundershowers over the far western parts.
Conditions in main agricultural production regions (20 - 26 February)
Maize production region:
Scattered thundershowers will occur over the area until Sunday (23rd). It will also be cloudy to overcast and cooler from Saturday (22nd) until Monday (24th). There may be periods of persistent rain or showers in some places especially from Saturday until early Monday. It will warm up again by early next week, with little to no rain expected during the first half of the week. Maximum temperatures over the western maize-production region will range between 23 and 30 °C, with lower maximum temperatures featuring especially during the weekend and early next week. Minimums will be in the order of 13 - 18°C. Maximum temperatures over the eastern maize-production region will range between 18 and 29°C (lower temperatures during the weekend) while minimums will be in the order of 8 - 15°C.
Cape Wine Lands and Ruens:
It will be sunny to partly cloudy and mild until Friday (21st). A cold front will cause light showers especially over the southern parts by Saturday (22nd). Strong south easterlies are expected following the frontal showers later on Saturday. It will warm up significantly from Sunday (23rd), with very high temperatures expected especially by early next week along the West Coast and Swartland, spreading further east by Tuesday according to current forecasts. Scattered thundershowers are expected to move into the area by Tuesday evening.
Possible extreme conditions - relevant to agriculture
According to current model projections (GFS model) of weather conditions during the coming week, the following may be deduced:
• Thundershowers over central and south eastern parts may have a tendency to become severe on Saturday (22nd).
• Significant 24-hour rainfall totals are possible over the eastern parts of North West, Gauteng, northern Free State, western Mpumalanga and southwestern Limpopo according to current forecasts on Saturday (22nd). These may result in flash floods in isolated areas.
• Significant 24-hour rainfall totals are possible over western Limpopo and surrounding areas according to current forecasts on Sunday (23rd). Where soil is saturated, these may result in flash floods.
• Cloudy to overcast, moist and cool conditions during the weekend and early next week over the eastern to north eastern parts may favour the occurrence of fungal plant pathogens.
• It will be very hot over the western interior as well as the western parts of the winter rainfall region early next week, spreading into the Karoo by Wednesday (26th).
• Strong south easterlies over the southwestern parts, especially by late Saturday (22nd), may be conducive to the development and spread of wild fires where vegetation is dry.
