MetService have issued a severe thunderstorm outlook for eastern parts of the South Island today.

They have yet to be upgraded to a watch or a warning however this is the latest information given.

A low is expected to move over the far south of the country around the middle of the day. Fronts associated with the low should move up the South Island during the day and there is a moderate risk of thunderstorms developing on a southerly change in the east from about Balclutha to Timaru late morning or this afternoon.

South of about Oamaru, if these thunderstorms occur they are likely to be accompanied by localised heavy rain with intensities of 10 to 15mm per hour and hail of 10 to 15mm diameter. North of Oamaru, localised heavy rain is also possible but the hail may be a little smaller at around 10mm diameter. There is a low risk of thunderstorms developing in the afternoon as far north as Rakaia and in the foothills of Canterbury.

WeatherWatch.co.nz is monitoring the situation closely