I have daily rainfall data for a given site going back about 30 years.
I have a building with an average daily demand for water of $L$ litres and a catchment of $A$ m$^2$ with a runoff coefficient of $c$.
How can I construct a model so that I can determine for a tank size T litres, The mean and variance of the
- days per year the tank will be empty
- Shortfall of water
- days per year the tank will overflow
- Amount of water that overflows
I have googled this extensively and found plenty of rules of thumb but noting that uses a probabilistic model.