Tropical torrential rain to hit North Island while the southern regions shiver

Parts of the North Island are being warned to brace for a sub-tropical drenching with heavy downpours so intense the crippling drought may be finally be broken.

Heavy rain is expected to hit the country tomorrow and last for up to a week.

At the same time the South Island is facing an autumnal cold snap with temperatures in some regions barely registering above single digits.

MetService said a low pressure system was expected to stay at the top of the country dragging humid air down from the subtropics and bringing rain across northern regions.

The downpours were expected be intense there was a possibility warnings would be issued for upper districts of the North Island.

The rain was also expected to fall over the Bay of Plenty, Gisborne, the Hawkes Bay ranges, and the central North Island high country but not to warning levels.

At this stage there was still some uncertainty about which areas would get the heaviest rain.

Weatherwatch.co.nz said the rain would finally bring relief to farmers in Northland and Gisborne signalling an end to the drought.

Meanwhile, temperatures in the far south had started plummeting with Dunedin and Invercargill reaching just 14C today and expected to be even cooler tomorrow.

Weatherwatch.co.nz said Christchurch, which has a high in the mid-20s today, would feel a noticeable nip overnight plunging to 14C before bouncing back later this week.