It is shaping up to be a damp weekend over much of the country for the first King's Birthday weekend.

MetService said Saturday appeared to be the best day, and any plans for Sunday onwards should include a raincoat, an umbrella and a check of highway conditions.

Forecaster Clare O'Connor said a front moving up the country from Friday would bring snow to the south and rain.

"No doubt this snow is good news for South Island ski fields with opening weekends fast approaching."

The North Island could also expect showery weather on Friday and strong winds in places.

Another front arrives on Sunday, with more wet weather set for the North and South Islands.

MetService's severe weather outlook also indicates a second period of snowfall on Sunday for South Canterbury and inland Otago, with a possibility of snow to lower levels.

"Everyone's going to get a bit of the wet stuff this weekend," MetService meterologist John Law told Morning Report.

"For Saturday, most of us should be in for a decent day," Law said.

"As we head towards Monday, perhaps head down to that western coast of the South Island, they've had a bit of wet run recently but for Monday they look like the pick of the spots in New Zealand."

MetService said the forecast was in line with a wetter than usual outlook for many regions, as was the case for May.

Among the rainfall records which were broken last month, the Hokitika Airport weather station recorded 618.2mm, which was the third-wettest month on record there since records began in 1963.

MetService report for Oamaru next 7 days