Issued at 5:02pm 13/04/2026

Valid from 5:02pm 13/04/2026 to Midnight 13/04/2026

Updated at 5.00pm to extend moderate risk into Southland. A series of fronts move onto and over New Zealand today, with temperatures cooling aloft over the South Island. For the North Island, there is a moderate risk of thunderstorms for much of the North Island as indicated of the chart with heavy rain 10 to 25 mm/h, along with a low risk of downpours boosting localised rainfall rates to 25 to 40 mm/h. The moderate risk of thunderstorms eases in western parts during the afternoon and evening, but a low risk remains. A low risk of thunderstorms covers remaining areas as indicated on the chart. Over the South Island, a series of fronts move northwards with the air aloft getting gradually colder. A moderate risk of thunderstorms extends through northern Westland, Grey and into the far south of Buller at night, while southern Westland and Fiordland are covered by a moderate risk of thunderstorms for the whole period. These thunderstorms will be accompanied by heavy rain 10 to 25 mm/h, but as things get colder over Fiordland and southern/central Westland, expect rainfall rates of 5 to 15 mm/h and hail of 5 to 15 mm in diameter. A low risk of thunderstorms extends further north through Buller, Nelson Lakes, the far northwest of Tasman and Marlborough Sounds. In the southeast of the South Island, as temperatures cool aloft, a front crosses the area and convergences set up in the east, there is a low risk of thunderstorms for South Canterbury, Otago and Southland in the afternoon and evening. However, for the far south of the Canterbury Plains, North Otago, Dunedin, Clutha and Southland, the risk is considered moderate for a time during the afternoon and evening. These thunderstorms may be accompanied by heavy rain 10 to 20 mm/h and small hail. There is minimal risk of thunderstorms or significant convection elsewhere during this period.

Issued at 10:10am 13/04/2026

Valid from Midnight 13/04/2026 to Midday 14/04/2026

A front and preceding trough move onto the North Island during Tuesday morning. There is a broad low risk of thunderstorms for the upper half of the island as indicated on the chart, but this risk increases to moderate for western and northern areas from Northland to northern Taranaki, also Coromandel Peninsula. If these thunderstorms occur they will be accompanied by heavy rain of 10 to 25 mm/h. A cold westerly flow covers the South Island, bringing showers to western parts along with a moderate risk of thunderstorms from southern Buller to Fiordland. These thunderstorms will be accompanied by heavy rain of 10 to 15mm/h and hail 10 to 15mm in diameter. A broader low risk area extends over Stewart Island and also further north through the remainder of Buller, Nelson Lakes and far northwest Tasman. There is minimal risk of thunderstorms or significant convection elsewhere during this period.

Issued at 6:48pm 13/04/2026

Valid from Midday 14/04/2026 to Midnight 14/04/2026

The front and preceding trough move over the upper North Island during the second half of Tuesday, and the unstable, cold west to southwest flow over the South Island spreads onto the North Island late in the day. Much of the North Island is covered with a low risk of thunderstorms, excluding Wairarapa and Wellington. However, there is a moderate risk of thunderstorms for Northland, Auckland, Waikato, northern Taupo and Coromandel Peninsula during the afternoon and for Bay of Plenty and far northern Gisborne/Tairawhiti during the afternoon and evening. These thunderstorms will be accompanied by heavy rain 10 to 25 mm/h. In the evening and at night, a front moves onto the west of the island, bringing a moderate risk of thunderstorms from western Northland to Taumarunui and Taranaki, also down to Horowhenua Kapiti Coast as indicated on the chart. These thunderstorms will be accompanied by heavy rain 10 to 15 mm/h and hail 5 to 10 mm in diameter. The cold westerly flow over the South Island turns more south to southwest. The moderate risk of thunderstorms affecting western areas from Fiordland up to far northwest of Tasman, and also parts of Southland and Otago, eases from the south during the afternoon and evening as indicated on the chart. These thunderstorms will be accompanied by heavy rain 10 to 15 mm/h and hail 10 to 15 mm in diameter. A broader low risk of thunderstorms covers Southland, Otago, South Canterbury and also over the Southern Alps and into Nelson Lakes. There is minimal risk of thunderstorms or significant convection elsewhere during this period.