Although a frost this late in the year was not ideal it was not unusual and Ms Wilson said the region could get frosts as late as December.
A Metservice duty meteorologist said the region would be looking at a fine afternoon today with lots of sunshine and very little wind.
He said this would continue into tomorrow morning with temperatures reaching the week's high of 23C.
A southerly change would then develop in the evening bringing rain which would ease off to showers on Thursday followed by some fine spells.
After the week's low of 4C overnight on Friday, southerlies would die out leading to a mostly sunny weekend with temperatures expected to reach 20C.
The southerlies would be especially strong around Cape Kidnappers, and snow could also settle on higher hills throughout the region.
A total of 25mm of rain is also expected over the week, though the Metservice duty meteorologist said the potential for more rainfall was there.