The next few days will see a continuation of the rainy conditions over the central parts of the country, intensifying somewhat during the remainder of the week and moving eastwards to be confined to the eastern and northeastern parts by Saturday (4th).
Sunny conditions should set in from Sunday onwards, but a significant cold front may invade the southern parts of the country by Monday (6th) according to current forecasts, bringing cold and windy conditions to the south. There is no indication yet of frost over the grain production region until at least Tuesday (7th).
The following is a summary of weather conditions during the next few days:
• General:
o The maize-production region should receive above-normal rainfall.
o The southwestern interior is expected to remain dry for the most part.
o Temperatures will be near normal over the eastern parts and winter rainfall region, but above normal over the western interior on average.
o It will be cool and wet until the weekend over most of the central to eastern areas with rain and thundershowers, especially over the central parts during the rest of the week - and confined to the northeast by Saturday (4th).
o Cold fronts will result in light showers over the winter rainfall region and Garden Route initially and again by Monday (6th).
o The frontal system on Monday will result in windy conditions with light showers along most of the southern to eastern coastal belt and adjacent interior.
o While the summer grain-production region should receive normal to above-normal rainfall, the southwestern areas including the winter rainfall region will be drier than normal for this time of the year.
o Strong southeasterlies are expected in the southwest on Wednesday (1st) and again by Monday and Tuesday (6th and 7th).
• Rainfall:
o Rain and thundershowers associated with cloudy and cool conditions will occur over the central parts on Thursday (2nd) and Friday (3rd).
o The cloudy and cool conditions with rain and thundershowers will relocate to the eastern parts on Saturday (4th).
o It should be dry over the country by Sunday (5th) and it is expected to remain dry until early next week over the interior.
o A cold front will bring light showers to the winter rainfall region (particularly the southern parts) by Sunday night (5th) into early Monday (6th), spreading eastwards along the Garden Route on Monday (6th) and finally into the Lowveld and the Eastern Escarpment on Tuesday (7th).
• Temperatures:
o It will be cool, cloudy and somewhat windy over the interior from Thursday (2nd) to Saturday (4th) with showers or thundershowers over the central areas, spreading eastwards and confined to the east by Saturday.
o It will be hot along the West Coast on Thursday, spreading to include also the southern parts (Karoo and surroundings) on Friday and Saturday (4th).
o It will become cold and windy in the south Monday (6th) and Tuesday (7th), with low minimum temperatures expected over the southern to southeastern high-lying areas around the Karoo and into Lesotho.
o It will be very hot over the Lowveld on Monday (6th) according to current forecasts.
o Maximum temperatures over the western production areas will be in the order of 20 - 27°C. Minimum temperatures over the western maize-production region will be in the order of 12 - 15°C.
o Maximum temperatures over the eastern maize-production region will range between 17 and 27°C (warmest conditions during the weekend ad Monday the 6th) while minimums will be in the order of 6 - 13°C - lowest minimum temperatures are expected on Friday morning (3rd).
Overview of expected conditions over South Africa during the next few days
An upper-air trough deepening and moving across the interior will result in showers and thundershowers during the week, moving out in the east by Saturday. An influx of moisture from the east until the weekend, together with extensive cloud cover, will dampen maximum temperatures somewhat. Another system may develop towards the middle of next week. A cold front moving into the southern and southwestern parts will result in significant cooling over the southern interior early next week. This will result in cold and windy conditions in the south by Monday (6th) and Tuesday (7th) over the southern interior.
Conditions in main agricultural production regions (1 - 7 April)
Maize production region:
It will be partly cloudy and warm to mild initially, becoming cloudy and mild to cool with showers and thundershowers especially from Wednesday (2nd) focussing initially in the west of the region. The cloudy conditions with showers and thundershowers will spread eastwards, and be confined to the eastern half according to current forecasts by Saturday. It will clear over the entire region by Sunday and become partly cloudy to sunny and warm over the entire region. By late Tuesday (7th), cool to cold air will invade the eastern parts, with some thundershowers expected over that part of the region. Maximum temperatures over the western production areas will be in the order of 20 - 27°C. Minimums will be in the order of 12 - 15°C. Maximum temperatures over the eastern maize-production region will range between 17 and 27°C (warmest conditions during the weekend ad Monday the (6th) while minimums will be in the order of 6 - 13°C - lowest minimum temperatures are expected on Friday (3rd) morning.
Cape Wine Lands and Ruens:
Strong southeasterlies are possible following the frontal system initially (Wednesday 1st) and again by Monday and Tuesday (6th and 7th). It will be sunny and warm for the most part and hot over the interior until Friday (3rd). It will become cloudy to partly cloudy by Sunday and Monday (5th & 6th) as a cold front moves through, bringing light showers especially to the southern parts according to current forecasts. Temperatures will also be significantly lower compared to the first few days from Sunday (5th) onwards. It should clear by Tuesday (7th), with strong southeasterlies in the southwest.
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:
• Persistent cloudy, wet and cool conditions over the central parts until Friday (3rd) may favor the occurrence of fungal plant pathogens.
• Hot (and at times) windy conditions are possible over the western interior until Saturday. This may spread onto the West Coast and Swartland on Thursday (2nd) ad Friday (3rd) and into the Karoo on Friday and Saturday (4th). Where vegetation is dry, these conditions may enhance the probability for the development and spread of wild fires.
• It will be very hot over the Lowveld on Monday (6th). This area will also experience a sharp drop in temperatures and a strong wind by late Monday into early Tuesday according to current forecasts.
• It will be cool to cold (and windy) over the southern interior by from Sunday (5th) evening, with frost possible in places over the southern to southeastern high-lying regions on Tuesday (7th) morning. The cold conditions may adversely affect small stock in the region.
• Strong southeasterlies are expected over the southwestern parts by Wednesday (1st) and again by Monday (6th) and Tuesday (7th). Where vegetation is dry this may lead to the development and spread of wild fires.
