The thunderstorms were due to hit Upper and Lower Hutt and Lake Wairarapa within the last hour.
The Ministry of Civil Defence and Emergency Management has advised residents in these areas to take shelter indoors away from windows, move cars away from trees, secure loose objects around properties, check gutters are clear, and be prepared to stop driving if necessary.
During and after the storm MetService also advises to beware of fallen trees and power lines and to avoid streams and drains as people may be swept away in flash flooding.
Earlier today, MetService extended the heavy snow warning in force for South Canterbury and North Otago to include Dunedin, as roads in the heart of the South Island closed because of snow.
❄ CRAZY SNOWY SCENES - current scenes at Craigieburn Valley Ski Area. A number of our local ski fields will be rubbing...
Posted by Canterbury Weather Updates on Friday, 9 August 2019
A heavy snow watch remains in force for the remainder of Canterbury south of Rangiora and Central Otago.
Road closures include SH73 from Springfield to Arthurs Pass (Porters Pass). SH73 from Arthurs Pass to Otira is closed to towing vehicles.
MetService meteorologist Peter Little said there had been some snow on the Crown Range and Lindis Pass in Otago overnight and more was expected. At 9am today the temperature at the top of the Crown Range Road was -1.4C.
Heavier snowfalls today could bring as much as 40cm of snow in areas above 500m, and snow warning are in place for areas above 300m.
NZ Transport Agency has urged drivers to plan ahead and take precautions.
Road Snowfall Warning for all New Zealand
Lewis Pass
Snow should continue to affect the road until Sunday morning. Until 9am Sunday,
expect a further 3 to 6cm of snow to settle above 600 metres, with lesser
amounts down to 400 metres.
Arthurs Pass
A few snow flurries may affect the road through to Sunday morning, but little if any should settle on the road and the warning is now lifted.
Porters Pass
Snow showers should continue to affect the road until early Sunday morning. Until 3am Sunday, a further 2 to 4cm of snow may settle near the summit of the road, with lesser amounts down to 600 metres.
Lindis Pass
Snow should continue to affect the road until Sunday morning. Until 9am Sunday, a further 4 to 6cm of snow may settle on the road above 500 metres, with lesser amounts down to 300 metres.
Haast Pass
A few snow showers may affect the road until early Sunday morning. Until 3am Sunday, 1 or 2cm of snow may settle near the summit of the road.
Crown Range Road
Snow should continue to affect the road until Sunday morning. Until 9am Sunday, a further 2 to 5cm of snow may settle on the road above 500 metres, with lesser amounts down to 300 metres.
Milford Road
A few light snow showers may affect the road through to Sunday morning. Until 7am Sunday, up to 1cm of snow may settle on the road above 600 metres.
Dunedin to Waitati Highway
Showers may turn to snow at times near the summit of the road until Sunday morning. Until 9am Sunday, 1 or 2cm of snow may settle near the summit of the road.
Main centre forecasts
Whangārei
Showers developing late morning. Northwest strengthening. High 19C, low 12C
Auckland
A few showers, more frequent from midday, possibly heavy and thundery with small hail. Northwesterlies strengthening morning. High 17C, 12C
Hamilton
A few showers, more frequent from midday with possible thunderstorms. Northwesterlies strengthening in the morning. High 16C, 10C
Tauranga
Fine morning. Showers developing in the afternoon, possibly thundery in the evening. Northwest developing, strengthening afternoon. High 17C, 12C
Wellington
Rain developing this morning. Possibly heavy and thundery from evening. Northerly developing, strong by evening. High 12C, 9C
Christchurch
Rain. Easterlies gradually strengthening. High 9C, 3C
DunedinRain setting in this morning, with snow lowering to 300m. Gusty easterlies. High 7C, 5C
- MetService