I'm an amateur, so I can't 'prove' anything, but my records indicate that 30 Sep 2009 had a strong South-Easterly wind in Cape Town.
As to whether it was excessive or not, perhaps you should contact the South African Weather Service, who could provide some documentary information (for a fee).
As you know Camps Bay doesn't have an 'official' weather station. The site windreport.co.za has a wind gauge at La Med:
windreport.co.za/wr_campsbay.shtml
windreport.co.za/wr_campsbaypast.shtml
You can try contacting them to see if they keep an archive of previous months.
I don't keep records from that location, but I will dig further into my archives to see if I have more specific data from other locations.