The ARC SA weather newsletter, Umlindi The Watchman, reports that, while below-normal rainfall was seen over large parts of the South African summer rainfall region, deficits were smaller than during most other summers associated with a strong El Niño phenomenon. What is known as the austral summer year (from July in the previous year to June in the current) 2015/16 has concluded.
The newsletter highlights that extremely dry conditions with several heatwaves during early to mid-summer were somewhat offset by wetter conditions since January. “Dry conditions during the previous summer, together with very high maximum temperatures were some of the exacerbating effects on the drought impact,” it states. Areas where the largest drought impacts were observed include the Lowveld of Mpumalanga, northern KwaZulu-Natal, and the southern and north-western Free State.
In contrast, areas where both rainfall and cumulative vegetation activity were above normal include large parts of Gauteng, central to western Mpumalanga, central to northern Limpopo, north-western Northern Cape and the Garden Route.
Normal to above-normal rainfall returns
Most importantly, normal to above-normal rainfall returned to the winter rainfall region in June 2016, after a lull during May. “Rainfall events associated with frontal activity over the south-western areas occurred regularly from the 9th of June,” the newsletter states. In much the same vein as the situation during the April-May period, yet another upper air cut-off low developed over the country in association with the frontal system by the 9th.
The low resulted in widespread cloudy and rainy conditions over the northern to south-eastern interior. A substantial fall of snow occurred over especially the north-western parts of Lesotho and adjacent South Africa in association with this system. – UMLINDI