The error message quotes the last valid storage discharge that was achieved in the run (e.g. just before the storage discharge table was exceeded) – so the number quoted in the error will be in the range of the table. It is likely that not every run in the Monte Carlo sample exceeds the range of the storage discharge table, which would explain why the single run doesn’t exceed the storage discharge table (e.g. it might not become a problem until a particularly rare rainfall or low loss is experienced).
I would recommend extending the storage discharge table (and the storage elevation table if used) and seeing if the model runs in Monte Carlo. By looking at the reported peaks in the summary file you will likely see for what runs the previous maximum discharge was exceeded.
If this doesn’t fix the problem please send through your model files to enquiries@dev7.preflight.com.au so that we have more information to work out a solution.
