A severe weather watch has been issued as Labour Day shapes up to be soggy and thundery for much of the North Island.

Auckland, Northland, the Coromandel and Waikato are all due for rain as a slow-moving front drifts south today, the MetService said.

MetService meteorologist Brian Mercer said a burst of heavy rain would move off the country late today, except for eastern areas like Gisborne where it would linger.

The heaviest falls are likely in the ranges of eastern Bay of Plenty during this afternoon and evening, with a heavy rain watch in place from noon. The front should clear the upper North Island by the end of the day.

The West Coast will be overcast with rain.

But Wellington is set to buck the trend, with long fine spells forecast. "Wellington should have quite a nice day tomorrow," Mercer said.

It was the same with the Wairarapa.

However Weatherwatch.co.nz warned the positioning of the low meant even a small change could result in wet weather for the capital.

Despite the wet, the weather should stay reasonably warm, with Auckland, Northland and Gisborne all reaching the high teens or even 20C.

The rest of the week is also set to be a mixed bag, with an active front crossing the country on Wednesday and Thursday bringing rain to large parts of New Zealand.

Friday looks settled but there is uncertainty towards the end of the week.

High cloud and rain have already marred Labour Weekend for much of the country, and the weather could spell more trouble for holidaymakers heading back from the Coromandel and Bay of Plenty today.