NSW weather live: Warragamba Dam overflowing as ‘mini tornado’ rips through western Sydney suburb

It’s going to be a long night for everyone. We are absolutely in uncharted territory.

Because all the hard surfaces that have popped up, we don’t know how the hydrology will react.

The bushland and farmland that used to be there soaked up the water, and needed to be saturated before flooding. But now because of all the paving and the houses, the runoff goes straight into the waterway.