Thunder and hail could again hit Canterbury today as an unstable airflow hits the area this afternoon.
Similar weather saw a tornado tear through Christchurch on Monday, pelting the city with hail, ripping off roofs and putting two people in hospital, while a waterspout also formed at sea.
And forecaster Niwa says there's more of the same on its way.
"Niwa's high resolution modelling is picking up on the risk for thunderstorms in Canterbury on Wednesday," the forecaster tweeted.
"The weather setup is very similar to that of Monday."
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MetService said coastal areas of the South Island had a moderate risk of thunderstorms today as a "bout of instability" worked its way up the east coast.
And Weatherwatch said showers would become heavy in Canterbury, Southland and Otago this afternoon, bringing possible hail and thunderstorms before clearing this evening.
"Unstable activity may be mostly inland about the foothills," Weatherwatch said.
The rest of the country is in for more settled weather, with the North Island due for a cloudy morning with patchy rain easing this afternoon and sunshine breaking through in many spots, according to MetService.
The rest of the South Island could mostly expect a mix of cloud, sun and occasional showers.
From Thursday the country can expect to bask in more settled weather, with many places seeing warmer than normal temperatures for the weekend.
Increasing cloud. A few showers from late morning, turning to rain in the evening, then clearing overnight with northwesterlies changing southerly. High 22C, Low 12C
Auckland Increasing cloud. A few showers developing from late morning, clearing evening with northwesterlies changing southwest. High 20C, Low 12C
Hamilton Morning rain, then increasing fine spells. Northwesterlies change southwest afternoon. High 20C, 7C
Tauranga Increasing cloud. One or two afternoon showers, then becoming fine evening with northwesterlies changing southwest. High 22C, Low 9C
New Plymouth Remaining showers clearing, then fine spells. Northwesterlies change southwest afternoon. High 18C, Low 6C
Napier Fine at first. Increasing cloud and a few afternoon and evening showers. Northwesterlies changing southwest evening. High 24C, Low 10C
Whanganui Remaining showers clearing this morning, then fine spells. Northerlies turning westerly this morning. High 18C, Low 9C
Wellington Becoming fine this morning as strong northerlies ease. Chance shower tonight with a southerly change. High 18C, Low 9C
Nelson Becoming fine this morning as northwesterlies change southwest. High 19C, Low 6C
Christchurch Showers, with possible thunderstorms and hail this afternoon, clearing evening. Southerlies turning easterly this afternoon, then dying out evening. High 16C, Low 4C
Dunedin Showers from midday, with possible thunderstorms and hail. Becoming fine evening. Southwesterlies. High 14C, Low 8C