The first of two significant fronts moving over the nation will arrive midweek and bring rain to most areas, as well as snow to around 1200m for the southern South Island.
Then, towards the weekend as we approach the official start date of winter, cold southwesterlies are set to pack a punch for New Zealand as the second front arrives.
Meanwhile, the weather for the past week which followed the trend for the month of May - which has been warmer and well above average daytime temperature - is set to move on.
The above-average autumn weather has also seen the country experience less rainfall than usual for May.
"The temperature in Wellington hasn't dropped below double digits since Monday morning, and is not expected to drop below 13C this coming week," Lee said.
"Today's maximum temperatures across the country aren't expected to be below 14-15C for the main centres, well above average for most of the South Island."