MetService meteorologist Alec Holden said he expected the mercury to reach the high teens by the weekend.
"Earlier this week, we had a large, cold pool of weather move up and over the country, bringing a major drop in temperatures and a brief return to winter conditions," he said.
Temperatures had dropped below zero in some areas, and heavy rain and snow fell over much of inland Otago and Southland, which was a shock to the system for many.
But now that the snow had passed, the southern regions would experience more northerly and northwesterly winds which would bring warmer air, he said.
"On top of the longer days with more sunlight that we are now experiencing, those winds from the northerly quarter will cause that temperature to bounce back.
"There will be occasional showers about the region, but they will be trucking on through — they won’t be hanging about for very long.
"Since we’re in spring, the weather is very changeable, so we’ll have these fronts and ridges moving in and out over the next week, but they should be very short-lived."
He said several fronts were expected to move across New Zealand today, bringing bursts of rain to western regions and strong northwest winds at times.
Then tomorrow, a moist northwest flow would affect the South Island, again bringing rain to western regions.
And on Sunday, another moist northerly flow was expected to affect the South Island, bringing rain to Fiordland and Westland.
Monday was looking pretty sunny, especially in Dunedin, he said.
"It looks like we will be starting off the next working week with temperatures up to 17°C around the southern regions, and that looks like it will continue."