Weather: Risk of flooding as heavy rain batters much of country, severe warnings issued

  • 21/04/2023

Much of the country is under severe weather warnings on Friday with heavy rain and gales expected to batter parts of central and western New Zealand.

The wild weather means surface flooding and slips are possible in some areas, according to MetService. 

"A low over the north Tasman Sea is expected to deepen and approach central New Zealand today, then move away to the east on Saturday," the forecaster said on Friday. 

"This low system is forecast to bring heavy rain and possibly severe gales to parts of central and western New Zealand from Taranaki down to Westland." 

A series of rain warnings and watches have been issued by the weather forecasting agency.

An orange rain warning is currently in place for Tasman northwest of Motueka and Westland between Otira and Bruce Bay until Friday night and Saturday morning.

An orange rain warning has also been issued for Mount Taranaki and Horowhenua, Kāpiti Coast, and the Tararua Range from late afternoon until Saturday.

Heavy rain watches are also in place for the remainder of Nelson/Tasman not under orange warning, Wellington, Wairarapa south of Greytown, Tongariro National Park, Manawatu, the Richmond and Bryant ranges, including the Rai Valley and the Marlborough Sounds, Buller and Westland north of Otira on Friday with some remaining through until Saturday.

MetService said it is important to note that even if rain in the watch areas (especially Wellington given the recent flooding) does not reach warning criteria there is still a risk of impacts such as surface flooding, slips, rising rivers, and hazardous driving conditions.

A strong wind watch has also been issued for Taranaki about and south of the mountain, Taihape and Whanganui north of the city from 7pm Friday until 7am Saturday. A strong wind watch has been issued for Coastal Southland and Clutha, including Stewart Island on Sunday.

On Sunday, a cold front is expected to move onto the South Island from the southwest, bringing westerly gales to the far south of the South Island. 

Here's MetService's extended forecast:  

Sunday

North Island: Scattered showers in the east and north. Partly cloudy elsewhere, with isolated showers late. South Island: Rain developing in the west. Partly cloudy in the east, with showers developing south of Christchurch. Strong southwesterlies developing, gale about the southern coast.

Monday

North Island: Scattered showers. South Island: Rain in the west clearing. Showers elsewhere, easing or clearing inland later.

Tuesday

North Island: Mainly fine, apart from a few showers in the south and east. South Island: Isolated showers in the east, clearing. Partly cloudy elsewhere. Late rain in the south and west.

Chatham Islands

Rain clearing to partly cloudy on Sunday as strong northwesterlies turn lighter southwest. Showers with strong southwesterlies from midday Monday and for Tuesday.