A severe weather watch for snow is in place from 2am to 8am on Wednesday and covers inland parts of northern Southland and the southern half of Otago.
Snow was forecast to lower to 100m and could briefly become heavy. Snow amounts could approach warning criteria above 400m during this time.
A snow watch was also in place for Fiordland south of Dusky Sound between 9pm tomorrow and 6am Wednesday.
A strong wind watch was also in place for much of Otago and Southland from today.
For inland parts of Otago northwest winds could approach severe gale in the 24 hours from 3pm this afternoon.
The same watch was in place for Southland west and north of Mossburn, and Fiordland, but from 9am this morning to 11am tomorrow.
A heavy rain watch is in place for the Otago headwaters for the 12 hours from 3am tomorrow.
Meanwhile, back ice has caused at least seven crashes on South Island roads so far this morning.
Senior Sergeant Craig Dinnissen, of Dunedin, said police were continuing to deal with crashes around the city due to icy conditions.
A Fire and Emergency NZ spokesperson said the crashes are mainly in Christchurch and the Tasman area.
Emergency services were called to a crash on Old West Coast Rd near Kirwee where a car has come off the road.
A patient was checked for injuries after a crash in Spencerville at 7.20am and another off-road crash was in Appleby in Nelson.
Fire crews worked to free a person trapped after a crash on State Highway 60, north of Takaka.
A St John spokesman said a person with moderate injuries has been transported to Nelson Hospital by helicopter.
Emergency services also attended a crash on Curletts Rd, near the motorway off-ramp, at about 7.50am.
The St John spokesman said no one was injured in the crash.
A police spokesperson said they want to warn motorists there is ice on the roads across the Canterbury District this morning.
"We urge you to take care and slow your speeds."
The NZTA is warning motorists to expect black ice on State Highway 74 near Kirwee as well as Dyers Rd.
The crashes came as much of the South Island woke to freezing temperatures on Monday.
The coldest place to be was in Twizel, which recorded a teeth-chattering -6.4C.
Comparatively, the warmest place in the country just after 6am was Methven, which clocked a somewhat cosy 13.4C.
Mostly fine conditions are forecast in Nelson, Marlborough, Canterbury, Otago and Southland.
MetService says there will be a few areas of morning low cloud or fog first off, but high cloud is expected to increase from the south; while northwesterly winds are set to strengthen in and around Southland.
Those in Nelson are experiencing about 1C to start off the day. In Blenheim, the temperature is -2C, 2C in Christchurch, -1C in Queenstown, 2C in Dunedin and 8C in Invercargill.
With NZ Herald
