Heavy snow and rain are predicted to lash parts of Canterbury, prompting a warning to hikers in the region.
An overnight downpour has led to some Christchurch roads being closed due to surface flooding - with warnings of more flooding to come.
Roads affected include Bellbrook Cres, Emmett St and Orcades St.
The MetService is warning areas north of Fairlie, along with coastal regions and the plains to brace for as much as 60mm of rain through to Monday night.
Trampers in the area to be on the lookout for rising rivers, floods and slips and the foothills from Porters Pass southward are expected to be hit particularly hard.
Meanwhile, snow is also expected to reach the same areas above 500m throughout the day, with up to 35cm possible at Porters Pass and up to 15cm further north.
"Heavy snow is likely to cause disruption to transport and place stress on livestock," forecaster Heath Gullery said.
The warning comes after more than a dozen vehicles were trapped by snow and had to be rescue in Central Otago over on Saturday night.
Lightning strikes nearly hit the 10,000 mark overnight as thunderstorms swept across the country.
The Christchurch City Council is on standby with pumps in flood-prone areas and ready to close roads if necessary after 21mm of rain fell overnight.
According to the MetService, 21mm of rain fell overnight, with 20mm more expected by nightfall.
Pages and Dyers Rds have surface flooding as does the Port Hills Rd, said the Christchurch Transport Operations Centre.
The city council has crews on standby to close roads if necessary, with temporary pumps already in the flood prone Flockton basin and Southshore.
Meanwhile, a fresh snow dump is forecast for parts of the South Island today.
At Lewis Pass, rain is expected to turn to snow today with 3cm-6cm expected to settle at road level.
Fresh snow is also expected at Arthurs Pass and down to 800 metres at Porters Pass, with up to 30cm expected at road level.
Most of the severe weather watches for the country have since been reduced or lifted now that the thunderstorm is heading off the edge of East Cape and out into the Pacific.
More than 100 lightning strikes were recorded in Auckland yesterday evening, with one video showing bolts of lightning hitting the Sky Tower, while thunder shook people's houses.
There was still a rain watch in place for the Tararua Ranges and Kapiti and Wellington due to another band of showers moving across from the Tasman.
However, it won't be as strong as the front that hit the area yesterday.
About 60mm - possibly up to 75mm - of rain is expected.
* Auckland 15 showers
* Tauranga 15 showers
* Hamilton 14 showers
* Wellington 13 rain
* Christchurch 8 rain
* Dunedin 7 showers, then fine spells
* Invercargill 8 showers, then fine spells
- Additional reporting: NZN