At first I thought it must be weather station failure, but then I checked the radar streamlines and what ever it was shows up there as well. I can only assume it must have been a strong local thunderstorm type of event, but it lasted quite a few hours.
I'd love to hear what the BOM make of it.
I would believe DI to be like that. From experience over the years it can turn nasty when it wants being exposed more than the other nearest places like rainbow beach.