Dunedin pelted with hail as severe thunderstorms bear down

Dunedin has been pelted with hail this afternoon as thunderstorms rumble across Otago and South Canterbury.

MetService earlier issued a severe thunderstorm watch for Canterbury Plains, Canterbury High Country, North Otago, Dunedin and Clutha.

“A few of these thunderstorms may be severe between 2pm and 9pm today with localised downpours of 25-40mm and large hail in excess of 20mm diameter. One or two small tornadoes are also possible.”

Rainfall could cause surface and flash flooding, while large hail could cause “significant damage” to crops, orchards, vines, glass houses and vehicles, the forecaster added.

MetService meteorologist Alec Holden said a large high-pressure system would move in from the west and perch atop the country for the weekend.

“The main line item for today is thunderstorms with hail.”

“Thunderstorms feed on warm temperatures and moisture near the surface – with plenty of both around, there is a very good chance we will see some form around the country.”

The forecaster said areas most likely to receive a “sparky shower and hail” from the afternoon were Canterbury, Otago, Inland Southland, Bay of Plenty, and Hawke’s Bay high country.

“Elsewhere, conditions are largely fine,” Holden said.

There has been a week of high temperatures, including a specific heat alert for Hastings as temperatures there skyrocketed over 30C. A heat alert was also issued for Ōamaru last weekend.

A severe thunderstorm warning was issued for Central Otago and Dunedin City at 3.22pm, to hit widespread parts of the region.

“These thunderstorms are expected to be accompanied by torrential rain and large hail,” MetService said..

‘More comfortable temperatures’ on the way

Holden said the warmer air mass assisting thunderstorms to form would be swept away on Friday, bringing milder temperatures ahead of a large high pressure drawing close to the country from the west. “Meaning, a noticeable drop towards more comfortable temperatures,” he said.

“People can expect a pretty nice day come the end of the working week, there will be showers around, but you would be unlucky to see one.”

The high-pressure system would then move atop the country on Saturday, creating “a very pleasant day across the country, excellent if you have some washing to do”.

“For Sunday, it should still be nice for most people, but northerlies build over the South Island, heralding a new front approaching the country from the west to kick off Monday.”