KEY POINTS:
The whole country is set for a temperature drop as a cold snap sweeps up from the south.
Forecasters say winter will fully kick in as the week continues, spelling an end to a mild autumn.
Forecaster Oliver Druce said snow would fall in many places and in Southland and Otago it could get down to sea level.
He said the North Island would not be as cold as the South Island, but a significant temperature drop would still be noticed.
MetService spokesman Bob McDavitt said the cold conditions were likely to spread north on Friday and Saturday with low-level snow affecting parts of Canterbury.
Meanwhile windy conditions were expected for Taranaki, Hawkes Bay and Wairarapa, as well as possible snow on the Desert Road on Friday.
Mr McDavitt said: "This is our first real taste of winter, and for many it will be a marked contrast to what was a mild May."
He warned strong winds, damp conditions and sub-zero temperatures would cause increasing stress to animals left unsheltered and also said driving conditions would be hazardous.
The weather change is good news for skiers in the far south, while Mr Druce says Ruapehu should also get a dumping over the weekend.
MetService issued a weather bulletin this afternoon saying Southland and Coastal Otago were set for another blast of severe gales tonight, with gusts up to 120km/h.
It is expected to become progressively colder during Thursday, with snow to low levels by Thursday evening.
FULL MET SERVICE FORECAST:
Gales
Southland, west to northwest winds are expected to rise to gale this evening in exposed inland areas with gusts 120k/mh.
From early Thursday morning expect westerly gales about the coast with gusts 120kmh but winds easing inland. Coastal gales should ease from about midday Thursday.
Coastal Otago from the Peninsula southwards, west to northwest winds should rise to gale in exposed inland places
this afternoon, with gusts 120 km/h.
From the early hours of Thursday morning, the gales should transfer
to coastal areas from the Peninsula southwards, and from 3am to noon
Thursday, expect gusts 120 km/h in this area. Winds easing a little from about midday.
Heavy snow warning
Areas affected: Inland parts of Southland and for south Otago including the Catlins.
Outlook
A very cold showery southwest flow should spread onto southern New Zealand Thursday morning. Snow showers are expected to lower to about 400m Thursday morning and to 100m Thursday evening.
From 6am Thursday to 6am Friday expect 20-25cm snow above 400m and lesser amounts settling down to about 100m. Further snowfalls are likely off and on throughout Friday and much of Saturday.
- NZHERALD STAFF, NZPA, NEWSTALK ZB
