Issued at 7:34am 31/07/2026

Valid from 7:34am 31/07/2026 to Midnight 31/07/2026

A disturbed westerly flow covers northern and central New Zealand for much of the day. Meanwhile, a cold front, followed by a change to strong southerlies, moves northwards over the South Island. There is a moderate risk of thunderstorms for coastal parts of Whanganui and Manawatu, plus Horowhenua north of Otaki throughout the day, also for southern and western parts of Taranaki, northwest Tasman, and Buller until late evening, and for the Grey and Westland Districts from the glaciers northwards until late afternoon, as depicted on the chart. Any thunderstorms that occur may be squally with gusts of 80 to 100 km/h. Brief heavy rain with intensities of 10 to 15 mm/h and small hail are also possible. There is a broader low risk of thunderstorms extending either side of these moderate risk areas, as indicated on the chart. For the remainder of Aotearoa New Zealand there is minimal risk of thunderstorms or significant convection today.

Issued at 7:07pm 31/07/2026

Valid from Midnight 31/07/2026 to Midday 1/08/2026

A strong and cold southerly change moves northwards over the lower North Island during Saturday morning, bringing a low risk of thunderstorms to mainly coastal parts of Manawatu, Whanganui, and South Taranaki before dawn. Meanwhile, a low is expected to approach the far north towards midday, with an associated trough affecting Northland during the morning. There is mostly a low risk of thunderstorms for Northland from dawn onwards, but for places about and north of the Bay of Islands and Hokianga Harbour the risk is considered moderate. Any thunderstorms that occur will likely be accompanied by heavy rain with rates of 10 to 25 mm/h, and small hail. There is minimal risk of thunderstorms or significant convection expected elsewhere in New Zealand during Saturday morning.

Issued at 7:10pm 31/07/2026

Valid from Midday 1/08/2026 to Midnight 1/08/2026

The low and associated trough continues to affect Northland during the latter half of Saturday, before moving away to the northeast. There continues to be a moderate risk of thunderstorms for places about and north of the Bay of Islands and Hokianga Harbour until early evening, then the risk decreases to low. For the remainder of Northland there is a low risk of thunderstorms during the afternoon and evening. Any thunderstorms that occur will likely be accompanied by heavy rain with rates of 10 to 25 mm/h, and small hail. In addition, for places about and north of Hokianga to the Bay of Islands there is a low risk of Severe Thunderstorms producing downpours of 25 to 40 mm/h during the afternoon and early evening. There is minimal risk of thunderstorms or significant convection expected elsewhere in New Zealand during this period