Thunderstorms, heavy rain forecast for Wednesday

Tuesday, 19 November 2019

Christchurch could be hit by another storm on Wednesday – just two days after getting bombarded with a tornado, strong hail and rain all within about 10 minutes on Monday.

Niwa said the city had another strong storm risk on Wednesday after Monday's storm caused more than 1100 lightning strikes over the city.

Monday brought wild weather to the garden city, injuring two people, ripping roofs off buildings and scattering debris – some contaminated with asbestos – through the air.

Niwa meteorologist Ben Noll said thunderstorms were likely to be 'widespread' across Canterbury, 'bubbling up' late morning or early afternoon on Wednesday.

**READ MORE:

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* Two people injured, buildings damaged, asbestos warning after tornado hits Christchurch**

'Unlike what you may have experienced on Monday, which was that lone thunderstorm, albeit quite a strong one, [on Wednesday] they might be a little more widespread across the region,' he said.

'The highest risk is probably across Canterbury, but certain folks in Otago as well couldn't rule out a few thunderstorms there and maybe even Southland.

NIWA's high resolution modelling is picking up on the risk for thunderstorms in Canterbury on Wednesday ⚡

The weather setup is very similar to that of Monday.

…when thunder roars, head indoors! pic.twitter.com/WAKuXJ0vII

— NIWA Weather (@NiwaWeather) November 19, 2019

'It's definitely a day you'd want to keep an eye to the sky and there may be more than one that rumbles through any given location.'

Noll​ said it was a similar set up to Monday, with good weather in the morning, turning extreme about lunchtime.

But the North Island wouldn't get much of it, he said. 

'[The South] has been holding the trophy for extreme weather events. In the North Island on Wednesday, [there'll be] nothing to write home about.'

​Noll's advice was 'when thunder roars, head indoors'.

'If you can hear thunder, you're close enough to be struck by lightning. We're in spring, there's volatility in the weather patterns.'

There is good news at the other end – Wednesday is the last day forecast to receive extreme weather in the near future.

CALM TUESDAY IN CANTERBURY

MetService meteorologist Curtis Hayes said the West Coast and lower South Island would bear the brunt of the country's bad weather on Tuesday.

'There's a front moving up the West Coast, and there's a chance of a little bit of rain spilling over in the afternoon, but it doesn't look too bad,' he said.

'We don't have a risk for thunderstorms in Christchurch at the moment. We do along the West Coast with the front and we do as well down south towards Dunedin, but when it gets to Christchurch, things look relatively weak.'

Christchurch was forecast for a high of 19 degrees Celsius and a low of 7C.

'This morning it's pretty blue skies out there and a little bit on the cooler side … [Tuesday] afternoon we'll see cloud increasing and we've got a few spots of rain in the forecast,' Hayes said.

The West Coast would have a 'typical rainy day' and a heavy rain warning was in place for the Arthur's Pass ranges until 9pm on Tuesday, bringing 130 millimetres to 180mm of rain. 

Thunderstorms could be expected in Otago between Oamaru and Balclutha, including Dunedin.

'We don't actually have that risk of tornadoes with that thunderstorm risk, but just heavy rain, small hail. There could be some flashes down there,' Hayes said.

There are no warnings in place for the North Island on Tuesday morning. Auckland is set for fine day with a high of 18C and a low of 12C. 

Clouds and strong northwesterlies​ are expected in Wellington along with some showers, a high of 15C and a low of 12C.