The dramatic moment a short-lived but damaging tornado formed in Christchurch has been captured on camera.
Footage posted to YouTube by Nick Muc shows debris flying through the air before the twister forms over businesses in Sydenham, sending roof panels flying.
Two people have been taken to Christchurch Hospital with moderate injuries after a the tornado touched down in the area around 2pm.
1 NEWS meteorologist Dan Corbett explained the conditions leading up to the wild weather this afternoon.
"Conditions were perfect for making a thunderstorm with very cold air in the atmosphere, then the southerly winds down low went up and met the cold air above.
"The unstable air then mixed with some spinning clouds that caused conditions to create a tornado.
"The thunderstorm cell has now moved offshore, but unstable conditions will still exist for the next few hours," Corbett warns.