"A bit of everything," he said.
"I'm not sure if they were all caused by the storm, but a good majority of them were."
Just before 6pm, WeatherWatch.co.nz said the worst of the thunderstorms - with isolated tornadoes - appear to have eased across Canterbury.
There was still a remaining downpour over Banks Peninsula and North Canterbury at the time, however.
"Further south, across the rest of Canterbury and into Otago, some very heavy showers still remain with bursts of strong wind and hail - otherwise the majority of both regions are dry," WeatherWatch.co.nz head analyst Philip Duncan said.
"A big hail shower hit parts of Dunedin just after 5pm and more are dotted about Otago and Canterbury as we head into the 6pm hour," he added.
Mr Duncan said today had seen a mix of good and bad news for the rural sector in the region.
"The rain was good, but hail and small tornadoes are clearly bad news if they directly hit seedlings or a glasshouse. So far WeatherWatch.co.nz has had no reports of damage from the farming community."
He said the chance of a tornado was still around, but the risk was likely easing as the region entered into the cooler hours of evening.
"The spring like weather will continue this week across Otago and Canterbury with more windy conditions and changeable temperatures."
Images and videos on social media also show multiple tornadoes travelling across Canterbury from Ashburton.
At 4.45pm this evening, WeatherWatch.co.nz confirmed that there were numerous reports of potentially multiple tornadoes across Canterbury, in Mayfield, Rakaia and the Ashburton area, as well as South Canterbury.
It estimated the tornadoes were at the lowest end of the scale - "most likely EF0 or potentially EF1 on the Enhanced Fujita Scale, which goes up to 5".
It said the main area of thunderstorms, hail and tornado potential was moving in towards Christchurch from the south.
"It's likely to peak and move through between 5pm and 6pm, then eases this evening."
Photographer Simon Baker tweeted photos that he took of tornadoes "somewhere between Rakaia and Ashburton".
Earlier this afternoon the streets of Christchurch were painted white with hail.
The MetService issued a severe thunderstorm watch for Christchurch and the surrounding areas just after 2pm.
"Cooling upper level temperatures over Canterbury and North Otago combined with daytime heating has led to the development of showers and a few thunderstorms," the MetService notice said.
The initial weather warning was put in place for Christchurch, Canterbury Plains, Canterbury High Country and North Otago.
MetService said at the time that there was also a moderate risk that one or two of the thunderstorms could become severe and produce large hail of 20-30mm in diameter.
It said there was still a high risk that thunderstorms could continue to develop this afternoon and evening.
Another MetService severe thunderstorm warning was issued at 3.25pm warning people in the Ashburton region of very heavy rain, large hail and possible tornadoes.
It said the weather radar had detected severe thunderstorms near Hinds and Lowcliffe.
"These severe thunderstorms are moving towards the northeast, and are expected to lie near Ashburton, Winchmore and Tinwald at 3.45pm and near Ashburton, Chertsey and Dromore at 4.15pm," the notice said.
It then added: "These thunderstorms are expected to be accompanied by very heavy rain, large hail and possible tornadoes."
At 4.45pm this evening, WeatherWatch.co.nz said there were numerous reports of potentially multiple tornadoes across Canterbury, in Mayfield, Rakaia and the Ashburton area, and South Canterbury.
It estimated the tornadoes were at the lowest end of the scale - "most likely EF0 or potentially EF1 on the Enhanced Fujita Scale, which goes up to 5".
It said the main area of thunderstorms, hail and tornado potential was moving in towards Christchurch from the south.
"It's likely to peak and move through between 5pm and 6pm, then eases this evening."
WeatherWatch.co.nz also tweeted that there were photos on social media of a tornado or two passing through that area.
Photographer Simon Baker tweeted photos that he took of tornadoes "somewhere between Rakaia and Ashburton".
MetService said the very heavy rain could cause surface and or flash flooding around streams, gullies and urban areas and make driving conditions extremely hazardous.
It said tornadoes could blow out windows, lift roofs, break large branches off trees, generate dangerous flying debris and blow vehicles off the road.
The Ministry of Civil Defence and Emergency Management also provided a list of things people should do as the storms approach.
It said people should take shelter - preferably indoors away from windows - and avoid sheltering under trees if outside. It said to move cars under cover or away from trees.
It also advised people to secure any loose objects around their property, check drains and gutters are clear, and be ready to slow down or stop if driving.
MetService added: "During and after the storm, you should also: Beware of fallen trees and power lines; Avoid streams and drains as you may be swept away in flash flooding."
Social media users made the most of the heavy hailstorm earlier this afternoon, posting pictures and videos of Canterbury's very own white Christmas.
Bob Reynard wrote that there had been a "massive hailstorm" in the Christchurch suburb of St Albans.
Another Twitter user, Bronwyn Hayward, wrote: "A white Christmas we didn't want in Canterbury..."
The hail storm was also felt wider in the region, with Brad Dennison writing on Twitter: "Massive hail stones in Timaru!!!"
St Martins resident Wendy Franklin said the sky turned black before large hail stones turned her property white about 2.15pm.
"There was a huge thunderstorm. The sky turned black and there was thunder and lightning and it looks like a white Christmas."
She took photos of the hail, that covered her back lawn and garden and looked like snow.
Although the hail was large and heavy, it had nearly melted an hour later.
Head weather analyst at WeatherWatch.co.nz, Philip Duncan, said the storm was part of the extended "spring pattern" that New Zealand is having this year, fuelled by El Nino.
"It encourages more changeable weather - mixing of cool air with afternoon hot air," he said. "The showers really explode into life over Canterbury in particular."
Mr Duncan said Canterbury quite often has the biggest thunderstorms in summer.
"The cold change was significant - Christchurch was just nine degrees an hour ago, now it's warmed up to 12. Was around 30 degrees at the end of last week."
He said Ashburton had a current temperature of 11 degrees and an incoming thunderstorm as of 3.40pm, with hail likely.
"A South East wind gusting 50km/h was blowing and could increase in localised downdrafts," Mr Duncan said.
He said WeatherWatch.co.nz categorised the weather as both good and bad.
While hail is bad for crops, the downpours are welcome news in the drought hit region, Mr Duncan said.
"Canterbury is mostly dry as of 3.40pm," he said. "But the showers moving into Ashburton - and popping up elsewhere - are significant and worth monitoring on the Met Service Canterbury rain radar. People who hear thunder nearby should remain indoors until they have passed."
Mr Duncan said he expected this unsettled spring pattern to continue into early January before the more settled summer weather kicks in.
