On Wednesday there will be a high of 21C, and the same for Thursday and Friday.
On Saturday the high is back to 22C.
MetService meteorologist Dan Corrigan says it's a very warm forecast for the start of May, with above-average temperature highs. Photo / Bevan ConleyThe average temperature for overnight lows for the start of May this year is about the same as in previous years, Corrigan said.
Monday's overnight low is a little on the warm side, with a low of 12C.
On Tuesday the overnight low drops to 10C, then down to 9C lows until Sunday evening.
Corrigan said MetService was not expecting any big weather events during the week for Whanganui.
On Monday there's a fair bit of cloud around, spreading off a decaying front, he said. That's hanging around the centre of the country.
"That front really weakens off Monday before it can reach the North Island," he said.
These clouds will bring rain to the West Coast on Monday, but they will peter out as they get sandwiched between two areas of high pressure.
"That high pressure is really the story for the next week, where we're looking at mostly fine weather after today's cloud clears."