Thank you for those photos Jimmy. Now I know what the late afternoon thunderstorm looked like on the outside. The storm was not very photographic where I live so I did not take any photos. However once overhead, it dropped quite a rain shower for several minutes including some small hail at first.
A person I know in Glenwood advised me that small hail fell at Glenwood and another weather enthusiast I know advised me that small hail about 0.5 mm in size also fell around Doonside for a short period as well.
A heavy rain shower ensured around Blacktown and Kings Langley and there were substantial downdrafts and leaves were being stripped from trees for several minutes.
Amazingly, I watched the thunderstorm rapidly weaken thereafter.
From 9 am 14/9/08 to 9 am 15/9/08, 14 mm of rain fell at Kings Langley (highest in Sydney), Blacktown 3 to 14 mm but that was dependant on how that late afternoon thunderstorm affected a specific locality, Seven Hills 8.7 mm, Baulkham Hills and Parramatta 9 mm, Only 3 mm fell at Box Hill and Toongabbie and 4.8 mm at Penrith.
While there were brief heavy showers after 2 pm 14/9/08, they did not produce substantial rainfalls. It was the 4.40 pm thunderstorm that produced most of the rainfall for the day where I live.
Harley Pearman