Severe rain watch for Whanganui this afternoon

The heavy rain watch goes from 11am on Tuesday to 9pm the same day. Photo / Bevan Conley

Heavy rain and thunderstorms are expected for Whanganui and other parts of the North Island this afternoon.

A heavy rain watch is now in force after Metservice issued the alert for Whanganui, Taranaki, Manawatū, Horowhenua, Kāpiti and the Tararua Range.

MetService meteorologist Alwyn Bakker said those in Taranaki and Whanganui would be the first to see the rain, followed shortly after by those in Kāpiti, Horowhenua and the Tararua Range.

He said the important thing about this heavy rain watch is the combined risk of thunderstorms, especially this afternoon and early evening.

"Because of the possible presence of those thunderstorms there could be localised downpours if the thunderstorm forms over an area and hangs around for a little while. So that's the particularly risky part of this watch.

"There's a risk of localised flooding if we do get those localised downpours."

Bakker said the best thing people can do is stay up to date with the latest forecasts.

"Because this is a watch rather than a warning it means that people should be prepared, but it's not the higher level of risks associated with orange warnings for example."

In some of those areas, the Metservice said rainfall amounts may approach warning criteria, for example 50 to 70mm in 9 hours.

The heavy rain watch goes from 11am on Tuesday to 9pm the same day.

Rain was expected to become heavier from late morning, with thunderstorms possible during the afternoon and early evening.

Metservice said a trough of low pressure could bring a period of heavy rain to the area around East Cape during Tuesday afternoon and evening.

The heaviest rain is expected in Bay of Plenty east of Opotiki and Gisborne north of Tolaga Bay and a heavy rain watch is in force for these areas.

Rain in Westland eased overnight and is easing in Buller this morning and the warning and watch for heavy rain in those areas has now lifted.