WELLINGTON, June 18 (Xinhua) -- Weather forecast on Tuesday signaled Wednesday morning to be coldest in 2019 so far for New Zealand.

Weather forecast institute MetService said a big freeze would hit the country overnight, with many locations throughout the South Island to drop below 0 degree Celsius.

It was reported that a large high rolling over from the Tasman Sea is locking in the cold air, shepherding in the chilly weather.

At 8:00 a.m. local time on Tuesday, Timaru Airport was the coldest place in the country after dropping to -3.3 degree Celsius. MetService predicted a similar start on Monday morning.

Queenstown could also see temperatures drop to -3 degree Celsius overnight, with temperature in Christchurch expected to reach -2 degree Celsius. Invercargill in the south island will plunge to -1 degree Celsius and Dunedin will see as low as 3 degree Celsius.

In the North Island, Auckland will expect the mercury to plunge to just 4 degree Celsius overnight. An overnight low of just 6 degree Celsius is forecast in capital Wellington.