Apart from some early-morning clouds and mild southeasterly breezes, Whanganui is in for a fine last day of summer on Monday.
A high of 21C is forecast with an overnight low of 10C, and sets a pattern for the next seven days.
"It's due to a high-pressure system over the region," MetService meteorologist Tuporo Marsters said.
"It's keeping the west coast sheltered while there's a bit of rain over on the east side. It promises a fine and settled week for the Whanganui region, but it doesn't make for very exciting weather news I'm afraid."
Autumn begins with a fine morning on Tuesday expected to reach a high of 23C, with some afternoon cloud and light southeasterly winds.