Just as parts of the South are cleaning up from widespread flooding brought by a two-day deluge, more severe weather is bearing down for some areas.
Dunedin got two months' of rain in less than two days last week, causing flooding and the declaration of a state of emergency.
Residents are now in clean-up mode, but MetService has forecast more rain on Monday afternoon, "possibly heavy and thundery with hail" before clearing in the late evening as fog sets in.
There was a small chance of rain on Tuesday and Wednesday for the city, but nothing like the downpour of last week that began on Thursday.
A heavy rain watch was in place for the headwaters of the Otago lakes and rivers, from 6am to 3pm on Tuesday; and for the Westland District and the Canterbury High Country, both from 8am to 5pm on Tuesday.
There would be periods of heavy rain with possible thunderstorms, and MetService warned of the chance of surface flooding, slips and difficult driving conditions.
The Clutha District was also hard hit by last week's rain, and dozens of roads were still closed on Monday morning.
A strong wind has been issued watch for coastal areas of Clutha and Southland, including Stewart Island, for 15 hours from 9pm on Tuesday to noon on Wednesday.
MetService said west to northwest winds could approach severe gale strength in exposed places, before turning southwest during Wednesday morning.
Heavy snow warning for Milford Road
A heavy snow warning is in place for Southland's Milford Road (State Highway 94) with MetService forecasting 15cm to 30cm of snow may settle on the road near the Home Tunnel, with lesser amounts to 600 metres from 5pm on Tuesday until noon on Wednesday.
The highway was open today but closed from East Gate (Hollyford) to Donne River (Westgate) at 5pm owing to forecast heavy rain tonight and the moderate risk of avalanche and heavy snow on Tuesday.
Milford Road Alliance said SH94 may briefly open on Tuesday afternoon before closing at night.
Cold front
A southwest flow would spread "over the entire country behind a front that crosses the North Island" on Wednesday, possibly bringing severe gale-force winds to the Canterbury High Country and Tararua District, and winds strong enough to warrant a warning to southern Fiordland and the Otago Peninsula.
NIWA described it as a "burst of cold air straight from Antartica".
"While the week starts with springtime warmth, a cold front will sweep the country on Wednesday, bringing brief burst of cold weather and a southerly change," it posted on social media.
"Don't put those heaters away as yet!"
A high was expected to arrive on Thursday, remaining over the country for a couple of days with "minimal" risk of severe weather. It might rain at the extreme north and south, but "no severe weather is expected".
By Saturday, there was likely to be "rain and strong winds to parts" of the South Island, but not bad enough to trigger a warning.
- ODT Online and RNZ
