MetService has issued multiple weather warnings and watches for Waitaki over the next few days.

An active front is forecast to move north over the South Island during Thursday and Friday, preceded by moist, gale to severe gale northwesterlies, and followed by a change to cold southerlies. Warning and Watches are in place for much of the South Island for heavy rain, heavy snow and strong winds.

Please keep up to date with the latest forecasts in case changes are made to these Warnings and Watches, or new areas are added.

Wind

Strong Wind Warning - Orange

Impact: Strong wind gusts could damage trees, powerlines and unsecured structures. Driving may be hazardous, especially for high-sided vehicles and motorcycles.

Area: Canterbury High Country

Period: 26hrs from 8pm Wed, 20 Sep - 10pm Thu, 21 Sep

Forecast: Severe gale northwesterlies with damaging gusts of 140 km/h in exposed places, mainly during Thursday afternoon and evening.

Area: Otago

Period: 19hrs from 8pm Wed, 20 Sep - 3pm Thu, 21 Sep

Forecast: Severe gale northwesterlies gusting 120 km/h in exposed places.

Rain

Heavy Rain Warning - Orange

Impact: Heavy rain may cause streams and rivers to rise rapidly. Surface flooding and slips are also possible and driving conditions may be hazardous.

Area: Headwaters of the Canterbury lakes and rivers south of Arthur's Pass

Period: 27hrs from 6pm Thu, 21 Sep - 9pm Fri, 22 Sep

Forecast: Expect 250 to 350 mm of rain about the main divide, and 100 to 150 mm within 20 km farther east. Peak rates of 15 to 25 mm/h about the divide. Possible thunderstorms. Rain turning to snow during Friday late morning and afternoon.

Area: Headwaters of the Otago lakes and rivers

Period: 24hrs from midnight Wed, 20 Sep - midnight Thu, 21 Sep

Forecast: Expect 220 to 300 mm about the main divide, and 120 to 180 mm within 30 km farther east. Peak rates of 15 to 25 mm/h, especially in possible thunderstorms.

Heavy Rain Watch

Period: 24hrs from 11am Thu, 21 Sep - 11am Fri, 22 Sep

Area: Otago excluding Clutha and the headwaters

Forecast: Periods of heavy rain, and amounts may approach warning criteria. Initially the rain will be in a northwesterly flow with heavier falls near the main divide, but widespread southerly rain is expected to spread north from Thursday afternoon. Note, a heavy snow watch is also in force for Central Otago and Queenstown Lakes from 6am Friday.

Snow

Heavy Snow Watch

Area: Inland Canterbury

Period: 15hrs from 9am - midnight Fri, 22 Sep

Forecast: Rain is expected to turn to snow above 200 metres. Heavy snowfall is possible above 400 metres, where amounts may approach warning criteria. Note, this Watch is likely to be upgraded to an Orange Warning in the next issue on Thursday morning.

Area: Central Otago and Queenstown Lakes

Period: 9hrs from 6am - 3pm Fri, 22 Sep

Forecast: Rain is expected to turn to snow above 500 metres. Heavy snowfall is possible above 700 metres, where amounts may approach warning criteria.