A tropically-fuelled cocktail of muggy conditions coupled with heavy rain and strong winds is set to sweep over New Zealand this weekend threatening travel disruption and flooding.

MetService has today issued a raft of warnings for the West Coast and bottom of the North Island ahead of a sub-tropical jetstream taking aim at the country.

The forecaster says both islands are in for an unsettled period of weather from today onwards with thunderstorms, heavy rain, strong winds, high humidity and hot temperatures.

Western and northern parts especially are in line for summer-like warmth and sticky conditions, with the humid air warm fuelling a spell of "active weather" featuring electrical storms.

It warned the strong winds bearing down on the capital on Saturday could affect travel while the heavy rain could see regions inundated by slips and flooding.

The weekend is shaping up to be a sticky, stormy affair for much of the North Island. Image / MetService

Temperatures are expected to rise on Friday with unusually warm weather expected this weekend and into next week.

Over the coming days the tropical airflow would see humidity increase, with Niwa advising those in the north to pull out fans from the back of the cupboard.

Auckland is set to enjoy a balmy 22C on Friday and Saturday, with an overnight low of 17C at the weekend - a drop of just five degrees.

Unfortunately the timing couldn't be worse for the Women's Rugby World Cup, with Auckland and Whangārei both in line for a wet weekend.

When the Black Ferns kick off on Saturday night at the Northland Events Centre in Whangārei it is likely to be a sticky 23C and showery.

Niwa said a sub-tropical jetstream would be fuelling strong fronts in the flood-ravaged West Coast.

The rain is expected to start falling in Westland from later tonight and not stop until late on Friday afternoon.

MetService said up to 160mm of rain is expected in the ranges, with a second period of rain likely during Saturday.

Buller is expecting a similar level of rain with a warning issued for 26 hours of non-stop rain from tomorrow lunchtime.

The forecaster warned the heavy rain might cause streams and rivers to rise rapidly and pose a threat of flooding.

Further north the capital is in line for winds approaching gale force affecting the region all day Saturday.

This afternoon the Tasman District Council warned residents to get prepared. While the burst of rain is not expected to be a large event, now was a good time to make sure everything was in order.

The Nelson region was inundated in August with days of rain that saw rivers burst banks, and widespread damage to homes and surrounding terrain.