Whanganui weather: Chilly morning well below city's average May temperature

Clear skies equal cold mornings for Whanganui. Photo / Bevan Conley

If you thought it was chilly in Whanganui on Wednesday morning you'd be right.

The temperature was well below the city's overnight average for May and the next two days will bring similarly chilly starts.

MetService meteorologist Ashlee Parkes said it was 4.6C at 8am on Monday, significantly below the minimum average overnight temperature for May of 8.9C.

"We currently have a ridge of high pressure dominating much of the country, and that has led to clear skies and little wind across many areas," Parkes said.

"This has allowed temperatures to cool quite significantly overnight."

Early morning conditions would remain cool for the next few days, Parkes said.

"Overnight on Wednesday we are going for a minimum of 4C again, and it will be 5C on Thursday night.

"It will then bounce back to around 9C heading into the weekend."

Parkes said cloud would begin to develop on Friday, with a couple of showers expected in the afternoon.

"The weekend is looking quite complex," she said.

"We have a front moving on to the lower South Island on Thursday evening, and that is going to track forward and bring those showers to Whanganui on Friday.

"Then there is a low forming behind that front in the Tasman Sea which is going to rapidly deepen.

"The low is going to create rain for many areas across the whole of the country over the weekend."

That rain would fall in Whanganui throughout Saturday, Parkes said.

"On Sunday the winds turn a little bit more northeasterly and you'll be more sheltered by the Central Plateau mountains.

"Hopefully that rain will clear up.

"The average daytime high for May is 16C and Whanganui will be following that average for the rest of the week.

"It'll be 16C on Thursday, 17C on Friday, and 18C on Saturday."