The round was interrupted by delays because of lightning and poor weather which forced the players off the course for nearly three hours in total.
Chief referee Cecil Wells was taking no chances with the safety of the players and was quick to get them off the course at the slightest hint of lightning.
Amazingly, only three matches failed to finish the round and will have to come back on Sunday and complete the round before play starts in the final round.
Kamungeremu fired the lowest round of the tournament thus far to move to 5-under for the tournament and leads by a stroke over Gerrie Coetzee and Andre Cruse.
'The weather put me off a little,' Kamungeremu said. 'But it was the same for everybody and I'm pleased with the way I played today.'
He carded six birdies - three on each nine - with a lone blemish being a double-bogey on the par-5 14th.
'My drive hit an anthill and kicked left which left me no shot with my second,' Kamungeremu said.
'I hacked out and ended up short with the next, which was followed by a chip and two-putt.'
The Zimbabwean, who plays out of the Sun River club, is one round away from his second victory as professional after he won the Botswana Open in 1997.
First round leader Graeme van der Nest from South Africa could only card an even-par 73 to remain at 3-under for the tournament and two-shots off the pace.