A front moves northwards across the South Island West Coast this morning and afternoon and onto Buller this evening, followed shortly afterwards by a more active cold front.
These fronts are forecast to bring heavy rain and thunderstorms to the west of the South Island, especially to Fiordland and Westland, as detailed in the latest SEVERE WEATHER WARNING and WATCH.
There is a high risk of thunderstorms about Fiordland this morning and afternoon and about Westland during much of the day, with a moderate risk extending to Buller later this afternoon. These thunderstorms are expected to produce localised heavy rain of 10 to 25mm per hour or possibly more about the ranges and there is a slight risk of a small coastal tornado.
The cold front and associated southwest wind change also brings a moderate risk of thunderstorms to Southland, Clutha and Dunedin this afternoon or early evening. Any thunderstorms here could produce localised heavy rain of 10 to 25mm per hour and also small hail.
A low risk of thunderstorms affects a broader area, including the remainder of Otago, the Canterbury High Country, South Canterbury and western Nelson, as indicated on the chart.
No thunderstorms or significant convection expected elsewhere.