The widespread convection peppers the underside of the upper anticyclone
with volatile warm to hot ascending air currents.
But as this new system builds and moves from the ocean to the continent, it is diverted by the strong upper anticyclone
. This is the main reason for the historical lack of moisture over most of Namibia.
A slight departure in this past week, saw recovery from the excesses of the week before, so enabling a core upper anticyclone
to take root above Botswana.
But, on the northern side of the upper anticyclone
, extensive convective activity seems set to persist into the weekend but, behind the departing trough, the upper high extends eastward squeezing the moisture belt ahead of it.
The persistent upper anticyclone
above Botswana is also complementary.
The upper anticyclone
has reformed further east and the weak trough line lies across Namibia.