A hyper-localised "mini tornado" has damaged a property in Pahoia, sending a dog cage flying, denting a roller door and uprooting trees.
Mike and Shirley Geros said it was late afternoon on Saturday when it started hailing at their place, and they noticed the clouds looked like they had been plaited.
"Next minute the wind came on so we shifted one of the dogs inside from out the front," Mr Geros said. "And it's lucky we did because it got a bit wild and the wind started spinning around."
The northwesterly wind rapidly changed to a westerly, then a southerly.
A big dog cage, which was installed over four dog kennels, was ripped off its foundations and flung down a bank to the neighbour's farm.
Mr Geros said the cage was "a pretty big unit". Some of the kennels had been blown over or had the roof blown off, but one remained intact and in place - with a very scared dog still inside. Another dog was found sheltering under a tree.
Mr Geros said they also had a roller door on a big shed cave in, a few young trees uprooted and a few tiles loosened on the roof.
Mrs Geros said it was all "quite frightening".
MetService severe weather forecaster John Crouch said it was possible a small, localised tornado could have formed in Saturday's thunderstorms.
"I can't really confirm a mini tornado but I wouldn't dismiss it. The thunderstorms were quite squally and there could possibly have been a small tornado."
The wind changes Mr Geros described made sense for a small tornado, he said.
He said the line of "quite active, squally thunderstorms" moved down over Auckland between 1pm and 2pm, then moved across the Western Bay between 3pm and 4pm before heading east and weakening when they hit the Eastern Ranges.
The thunderstorms brought wind gusts of 70km/h to 80km/h, heavy rain and some hail.
Squalls were short - 5 to 10 minutes - gusty bursts of wind caused by the air "falling out of the thunderstorm and hitting the ground then sort of running away", Mr Crouch said.