Near-freezing temperatures are set to grip Northland later this week with a possibility of frosts in inland areas.
The mercury is expected to plummet to 3C in places like Kerikeri and Kaitaia overnight on Friday and MetService is advising people to be prepared for a nippy Saturday morning.
Northland will experience daytime temperatures of between 15C and 17C most of this week, with overnight lows of mostly 6C to 7C except on Friday evening.
A cold showery southwesterly flow brought heavy snow to about 600m in parts of the lower South Island overnight on Monday.
MetService meteorologist Tui McInnes said although Northland would not experience anything near what the Otago and Canterbury regions were facing, frosts were a possibility especially on Saturday morning.
In April, parts of Northland were blanketed in icy whiteness as up to 200 lightning strikes and intermittent rain brought a heavy hail storm to the region. Parts of Waipū and areas in and around Mangakahia particularly got a heavy blanket of hail.
McInnes said the air in Northland was warm enough to diminish the risk of snow.
"But there's a possibility of haily showers because the current system is quite showery. The southwesterly is quite cold, that helps to generate hail.
"Places like Kaitaia and Kerikeri will get quite cold overnight Friday with an overnight low of 3C which will be a good set-up for frosts inland. Areas near the harbour will be less likely to get that cold."
However, McInnes said the cold snap was likely to be short lived, with a front moving down New Zealand late on Saturday or on Sunday that would settle things down.
Temperatures would rise slightly as rain came through on Sunday, he said.
The cold, wintry outbreak moved across the South Island, with the cold front just moving over central New Zealand yesterday morning. Ahead of the front over the North Island there was unstable air with a moderate risk of thunderstorms for both the western North Island and the east coast.
Whangarei recorded the highest temperature, 12.8C, at 12.30pm yesterday.
Rain is expected to ease off to showers on Monday but the forecast for the rest of next week in Northland is for fine weather.