It's been a quiet summer as far as trough activity
Recent model runs (GFS and NAVGEM up to 00Z on Sat 11th) continue to converge slowly (particularly at the longer durations). There seems to be an increased likelihood of a cutoff-low (somewhere) along the Cape coast during Thurs 16th and Fri 17th.
All model runs show a period of intense cold, and persistent unsettled weather during this event. Snow is possible! See: http://www.snow-forecast.com/maps/static/southafrica/next3to6days/snow
The following NAVGEM charts at 00Z on Thurs 16th and 00Z on Fri 17th show potential development of this cutoff-low. The GFS model is more fickle (as always), but is generally consistent with this NAVGEM scenario.
This GFS ensemble ‘spaghetti’ chart shows considerable uncertainty in the position of the cold-core upper-trough (500hPa level) at 12Z on Thurs 16th (5.5 days or 132 hours head), but gives a stronger ‘signal’ than yesterday’s model runs.