MetService forecaster Tuporo Marsters said the weather events were not tornadoes.
"They were dust devils. A dust devil is dry - it doesn't have any moisture in it."
Tornadoes developed from cold air, had "a lot of rain in them" and were much stronger, he said.
The dust devils were caused by surface heating, which caused air to rise quickly. When it met strong, high winds a spinning effect was produced.
Davis Auto Electrical manager Brendan Davis said "massive amounts of dust" needed to be cleaned from outside the shop, in Cromwell's industrial area, yesterday.
"You could take a stick and write your name in it. At the time, you could barely open your eyes."
During the event a metal roof from a neighbouring lot flew off a shed and did "two somersaults" before landing next to his shop.
Cromwell chief fire officer Steve Shaw said the events were not uncommon in the town.
"They've been happening in the 20 years I've been here."
Delta operations manager John Campbell said several hundred customers in Bannockburn, Cairnmuir, Hawksburn and Ripponvale were affected by a power outage after an Aurora Energy pole fell.
"Delta was able to isolate the fault, but 37 customers remained off until the power pole could be replaced. Power was restored to all customers at 10.36pm."
In such an event, people using medical equipment relying on electricity should ensure they were prepared for power disruptions and call their health provider or 111 if there was an immediate health threat, he said.
During outages, people should switch off appliances at the wall so they wouldn't be damaged when power was restored.
Summerfruit New Zealand chairman Tim Jones said the wind did not damage cherries but the 45 South packhouse he managed briefly lost power.
In 2012, what was thought to be a dust devil ripped out a tree and parts of a roof on a Cromwell property.
In January 2009 a similar event tore off part of the Bannockburn Hotel's roof, and in July that year, a whirlwind hit an area north of Cromwell, destroying an implement shed and lifting off a barn roof.