A "short but intense" burst of rain hit Dunedin on Monday, causing flooding to parts of the south.
The fire services says it received more than 45 callouts to damaged property, mainly commercial buildings, because of heavy hail and rain.
The Dunedin City council was called out to at least 14 houses that were affected by flooding and water damage, estimating a downpour of at least 9mm of rain in 15 minutes.
Some city buildings were evacuated, including the Dunedin City Library which was evacuated for 45 minutes after water began leaking inside.
Surface flooding has caused problems across the city from north Dunedin out to Mosgiel, as well as reports of thunder and lightning during the storm.
Dunedin resident Carmel Callahan says the storm came out of nowhere.
"A massive lightning bolt came straight down right outside my house and cracked some sparks," she says.
"It looked like it hit my garage."
The council says flood waters are now receding but motorists should be alert for any road closures and drive to the conditions.