Make the most of the warmer weather this week because temperatures are expected to plummet this weekend.
MetService meteorologist Peter Little said strong northwesterlies will pass over the South Island during the next few days, bringing temperatures up to 17 deg C today and tomorrow.
"There is high confidence that a heavy rain warning will be needed for Fiordland during Thursday and Friday, and also for Westland south of Otira and the headwaters of Canterbury lakes and rivers from late Thursday to early Saturday.
"With regards to strong winds, there is moderate confidence of severe northwest gales in Fiordland, Southland and Clutha on Thursday and Friday, while there is high confidence of northwesterlies rising to severe gale in exposed places of Otago (excluding Clutha) on Friday and early Saturday."
Later on Saturday, a complex trough was expected to arrive from the southeast and pass over on Saturday and early Sunday.
Little said it would be driven by a high to the south of the country which would "just sit there, feeding in this cold air from down south", bringing more heavy rain to much of New Zealand and possibly snow to low levels.
"There is some pretty cold weather on the way. At the moment, snow flurries are possible down to 500m in the Dunedin area."
He said the cold front would weaken on Sunday, and a ridge of high pressure would follow next week, potentially bringing morning frosts and daily highs of about 7 deg C.
Temperatures were not expected to return to double digits until Friday next week.
Friday
South Island: Rain in the west and south, possibly heavy, but mainly fine in Canterbury and Marlborough. Gale northwesterlies, possible severe gales.
Saturday
South Island: Rain for the west coast and far south. A few showers elsewhere.
Sunday
South Island: Rain or showers for Marlborough through to Southland. Snow to 1000 metres in the north lowering to 600 metres in the south.
