Ah yes Nakuru -almost booked a holiday there once !
Glad you had a great time TG
Funnily enough I was talking at the gliding club today to a guy that had flown out in Namibia. He reckons 12-13 thousand foot thermals are quite normal.
At Gwelo we were at approx 4,500' ASL - the day/night temp difference could be as much as 30 deg...which is great for cloudbase,I certainly know of definite 12,000' base in zim...although never quite got there myself