Weather update: Further tornadoes possible, thunderstorms and heavy downpours expected

Thunderstorms and heavy downpours are expected for the rest of the week with more tornadoes possible in the upper North Island tomorrow.

A heavy rain watch is in force for some western regions of the North Island until 6am tomorrow, as bursts of heavy showers could mean accumulations could reach warning criteria. What exactly is the threshold for a heavy rain warning? Find out here https://t.co/NRnmUE65Nn ^AC pic.twitter.com/7An9FXcPb6

— MetService (@MetService) August 20, 2018

WeatherWatch has reported that with so much instability tornado risks for the upper North Island on Wednesday could not be ruled out.

Another surge of heavy downpours was expected to follow on Thursday with hail and possible thunder.

"This is when a bulk of the low pressure finally shifts entirely over to the eastern side of NZ and encourages a colder southerly flow up the country," WeatherWatch has reported.

It says this process could bring another burst of downpours and snow may affect the Desert Rd on Thursday evening or early Friday.

Snow flurries were likely across the Southern Alps and may briefly affect alpine passes.

Today's temperatures will be warmer than average across the country.

On a brighter note, sunshine should follow by Sunday through to the middle of next week.

Meanwhile locals are working to repair the aftermath of the two tornadoes that hit on either side of the North Island last night in Ōhope and New Plymouth.

Ōhope resident Andrea Inman described looking out her window with her daughter watching the tornado move closer towards their house before a roof shot above them.

She said it was a disaster zone this morning but from about 6.30am there had been about 50 people from the community helping with the clean-up.

The tornado, which struck the eastern end of Ōhope at 5.45pm yesterday, significantly damaged at least two properties and caused moderate damage to a further four properties.

The clean-up and assessment of damage begins this morning at the Surf and Sand Beachfront Venue in Ohope. Photo / Alan Gibson

The most significant damage was at the Surf and Sand conference centre, and at least one nearby home in Harbour Rd, Whakatāne District Council said this morning.

"Fire Service units from Ōhope, Whakatāne, Edgecumbe, Tāneatua and Rural Fire attended to assist with securing damaged properties and Police patrols were increased overnight to provide additional security," a council spokesman said.

Meanwhile, more than 10 houses were also badly damaged in New Plymouth after a second unrelated tornado ripped through.

Last night Fire Emergency New Zealand (FENZ) crews from around the New Plymouth area attended 37 tornado-related incidents.

"Eleven houses were assessed to have major damage and another 20 were assessed with minor damage," a FENZ spokeswoman said.

New Plymouth was struck by one of the tornadoes around 5.30pm, uprooting trees and tearing iron roofing from houses.

Police and Fire and Emergency last night set up a command centre at the intersection of Belt Rd and St Aubyn St in the city.

Both emergency services would be door-knocking to check on the welfare of those in the affected areas.

The roof of Odette Bastin's home was sucked up by the tornado causing significant damage.