Issued at 7:53am 18/09/2026

Valid from 7:53am 18/09/2026 to Midnight 18/09/2026

A low pressure system over northern New Zealand moves slowly away to the east. However, residual moisture and daytime wind convergences are expected to produce showers over central and northern regions. For Northland, Auckland, Coromandel Peninsula, and from Waikato across northern Taupo to the ranges of the Wairoa District and southern Gisborne/Tairawhiti, there is a low risk of thunderstorms this morning but a moderate risk this afternoon and early evening. For Bay of Plenty, there is a moderate risk of thunderstorms through into the early evening. During the afternoon and early evening there is a low risk of thunderstorms for Waitomo, Taumarunui, Taupo, Taihape, northern Manawatu, northern Tararua District, parts of Hawke's Bay, and the remainder of Gisborne/Tairawhiti, as drawn on the chart. Any thunderstorms that occur will likely be accompanied by brief heavy rain with intensities of 10 to 25 mm/h, and small hail. There is minimal risk of thunderstorms or significant convection elsewhere in New Zealand today

Issued at 8:22am 18/09/2026

Valid from Midnight 18/09/2026 to Midday 19/09/2026

There is minimal risk of thunderstorms or significant convection during this period.

Issued at 6:56pm 18/09/2026

Valid from Midday 19/09/2026 to Midnight 19/09/2026

A cold front is forecast to move northwards over southern New Zealand during the latter half of Saturday, followed by a strong, cold and unstable west to southwest flow. From late afternoon, there is a moderate risk of thunderstorms for parts of Fiordland south of Milford Sound, Stewart Island and coastal Southland, and then remaining southern parts of Southland and southern and eastern Clutha in the evening and at night as depicted on the chart. Thunderstorms that occur may be squally with strong wind gusts of 90 to 110 km/h, produce brief heavy rain with intensities of 5 to 10 mm/h, and small hail. There is a low risk thunderstorms that extends northwards to include the remainder of Fiordland and much of Otago from evening, as drawn on the chart. There is also a low risk of thunderstorms for Banks Peninsula at night. There is minimal risk of thunderstorms or significant convection elsewhere during this period.