The temperature fell to about 1 degree Celsius in Marlborough overnight Monday, but no frost was recorded, says Climate Consulting climatologist Stu Powell.
A frost at this time of year when grapes are nearly ready to harvest would be of concern to grapegrowers as it could damage the vines' leaves which would slow ripening.
Mr Powell said it was cool on Monday night, but did not fall below 1C.
"It got very cool in Upper Awatere and parts of Waihopai Valley as well."
The next five days were going a "little unsettled", he said.
"The next two to three days will be windy . . . [but] it would start to settle down next week."
He was not expecting a frost this week.
"I don't see any frosts in the horizon . . . We've been through the coldest part."
Morton Estate Wines' Awatere Valley vineyards general manager Tom van der Burg said the temperature fell to 1.3 C, and they turned on wind machines as a precaution. The machines had been on three times this year, Mr van der Burg said.
"We had a cold snap in January and we've had one every month since then. It's a bit unusual."
- The Mirror
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