Whanganui weather: What to expect for the weekend and Queen Elizabeth II Memorial holiday

It's a matter of "picking your opportunities" over the long weekend, MetService says. Photo / Bevan Conley

There is a bit of everything on Whanganui's weather front for the long weekend.

MetService meteorologist Peter Little said there was a risk of thunderstorms, some severe, in Whanganui on Friday afternoon and evening.

"They are quite slow-moving, so they have the potential to dump a lot of rain in one place, while a couple of kilometres down the road could be dry.

"We are expecting that risk to continue through Friday but skies should brighten up in the afternoon."

A band of rain covered much of the south of the North Island on Friday, thanks to a low pressure system to the east of the country.

A daytime high of 20C was expected on Friday.

"That low-pressure system is slowly moving southwards but because the atmosphere is unstable, that will allow some showers and thunderstorms to potentially develop," Little said.

The low would eventually be replaced by a ridge of high pressure.

"Some southerlies will bring showers through Saturday but things start to brighten up on Sunday," Little said.

"Winds turn more northeast on Monday, which is a great direction for Whanganui, which is very sheltered.

"That will see the temperature hit 20C [Monday] and even 19C on Sunday. At this time of year, you would usually be looking at around 16C."

There would be a high of 17C on Saturday.

Little said it was a matter of "picking your opportunities" over the long weekend, especially with the chance of thunderstorms.

"There will certainly be periods of fine weather as well. Monday is looking like a cracker."

Overnight lows for the weekend would be between 8C and 10C from Friday to Monday.

"It's usually around 9C at this time of year so that is pretty average," Little said.

"Those daytime temperatures are slightly above average though. It's T-shirt weather, which is perfect for spring."