This is very interesting reading and some nice pics! The funny thing is though your storms seem quiet dry with very low rainfall amounts, is this typical? Often when we have thunderstorms in the UK you hear about places getting 25mm to 50mm everytime we have an outbreak, most years you hear about some place getting 100mm+ from a storm although for one particular place to get that much from just one storm is rare, but it happens. I'd usually expect an average of 10mm to 25mm from a summer storm. Most of your storms seem to have quiet low rainfall amounts though often less than 10mm. Just wondering if your storms are perhaps more spectacular in terms of lightning etc but not as high in precipitation? I imagine it varies locally a lot eg North-East Queensland has a very high summer rainfall.