Whanganui weather: 'Pretty tropical' June days on the way

Early June typically reaches an afternoon maximum temperature of 15 degrees in Whanganui. Photo / Bevan Conley

Following the weekend's chilly mornings, temperatures in Whanganui are expected to climb above 20C this week - an unusually high temperature for June.

MetService Meteorologist Dan Corrigan said it was usually cold and bleak at this time of year, but the next few days would be an exception.

Corrigan said Whanganui was expected to hit 21C today and 20C tomorrow .

"To put that in perspective, normally a day in early June in Whanganui is looking at an afternoon maximum temperature of 15C," Corrigan said.

"So 20C is pretty tropical compared to that."

There is an overnight low of 12C expected for tonight , which is also above average for early June.

Corrigan said the warmer weather was due to a northerly wind flow, bringing warmer air down from the north.

The winds would remain north-westerly throughout the week, picking up to strong winds on Thursday.

Bouts of rain would be on and off during the week as systems from the Tasman come in from the west, Corrigan said.

The rain was expected to carry through to next weekend, but Corrigan said this could change as weather systems change throughout the week.

Last weekend, according to the Whanganui City Weather Station, temperatures got down to 3.8C at around 4am on Sunday, and it stayed at that temperature until around 8am.

Temperatures didn't reach 10C until midday, with a brief 17C between 2pm and 4pm.

"Because of these short days in June, it was quickly back on a downward trend," Corrigan said.

"At this time of year the days are short, the nights are long and the sun's rays are quite weak."