“Another high-pressure system is coming across though, so early next week will still feel pretty cold.”
Monday’s daytime high is 17C, dropping to 16C on Tuesday and 15C on Wednesday.
Thursday and Friday’s daytime highs are 17C.
Overnight lows will be between 4C and 5C for the rest of the working week.
“That could potentially drop lower depending on how things go,” O’Connor said.
“There will be some sun so things will warm up fairly easily during the day, unlike places like Central Otago which has been under fog for a few days and is barely getting above zero down there.”
Whanganui recorded its third-warmest May since 1937, with a maximum air temperature of 24.7C on May 1 - the highest on record.
A total of 62mm of rain was recorded on May 20, the wettest day on record for that month.
Autumn temperatures were above average or well above average across nearly all of the country.