"It's going to stay that way pretty much for the entire weekend and into early next week, where the winds will die out around Tuesday and turn around to westerlies."
Glassey said a low-pressure system in the Tasman Sea was approaching the North Island but most of the heavy rain it brought would be for the upper North Island.
"So while Whanganui should see some rain, it won't be anywhere near the amount we're going to see for the upper North Island."
He said Friday reached its maximum temperature of 16C at 1pm.
"It's now dropped to 13C, where it will probably stay," Glassey said yesterday.
"Saturday will reach 14C, and Sunday looks like it will jump back up to 20C."
He said MetService forecasted Friday evening to get down to 8C overnight, and between 10C and 11C for Saturday and Sunday night
"So nothing out of the ordinary."
Niwa's seasonal climate outlook for October to December stated temperatures were 70 per cent likely to be warmer than average in the North Island.
It said more northeasterly winds and marine heatwave conditions would sometimes result in unseasonable warmth and humidity.
"Rainfall totals are about equally likely to be near normal, and fewer westerly winds will increase the risk for dry spells."
It said air pressure was forecast to be higher than average across New Zealand.
"This will likely be associated with less frequent westerly winds, more northeasterly winds, and the potential for longer dry spells in western areas.
"October may have variable temperatures before a more marked rise in November
and December, along with an increase in humidity."
