MetService forecaster Aidan Pyselman said a cold front moved over the lower South Island yesterday morning, bringing rain.
At its heaviest 13.8mm of rain fell between 11am and 1pm, he said.
"That’s pretty decent — anything over 6mm an hour is heavy rain, so during that hour between 11am and 12pm it was 7.6mm and the following hour it was 6.2mm."
The rain was followed by a reasonably strong, cold southwest change.
Showers were expected to persist until about noon today.
Despite a fine afternoon and evening, today’s temperature was expected to reach a "pretty frigid" high of only 11°C as a cold snap started to spread up the country.
A typical daytime temperature for this time of year was about 18°C, Mr Pyselman said.
Yesterday’s rain was accompanied by thundershowers and the St Clair Hot Salt Water Pool was closed for an hour yesterday because of concerns about lightning, staff at the pool said.
