The threat of severe thunderstorms has been lifted for Dunedin, but the MetService now says they could hit North Otago bringing a chance of tornadoes.
The MetService today updated its thunderstorm outlook and is still saying thunderstorms are possible across much of the South Island.

MetService thunderstorm outlook for Friday
However, it has upgraded its warning for North Otago and Canterbury south of Christchurch saying there is a risk thunderstorms there could become severe this afternoon and evening bringing localised downpours of 25mm to 40mm per hour, hail greater than 20mm in diameter and the possibility of small localised tornadoes.
There was a moderate chance of non-severe thunderstorms in most of the East Coast of the South Island from from Waitaki northwards.