Upper Hutt lashed with up to 20 millimetres of rain in minutes in Wednesday night's flash flood

Some areas of Upper Hutt received up to 20 millimetres of rain in minutes during last night's heavy downpour, according to MetService.

The downpour around 7pm caused roof tiles of the Countdown Supermarket in Maidstone to fall down and several streets to flood.

MetService meteorologist Kyle Lee said it was a fast-moving storm.

"It was a solitary storm over the Upper Hutt region.

"The rest of the region got a few showers, but nothing heavy."

Lightning and thunder were also reported in parts of Upper Hutt, and there were reports of hail in the suburb of Silverstream.

The region has had a better day today and is expected to remain relatively fine over the weekend.