According to the MetService, a deep subtropical low is forecast to pass to the northeast of the North Island during Saturday (20 July), with associated troughs expected to bring a period of heavy rainfall to parts of northern New Zealand plus western Tasman. Another trough associated with the low, which is preceded by easterly gales, is forecast to move southwards over the Chatham Islands on Sunday morning (21 July).

• A heavy rain watch has been issued for Northland, Auckland north of Whangaparaoa Peninsula, and Great Barrier Island from 2000 hours on Friday (19 July) till 0800 hours on Saturday (20 July).
• Warnings have also been issued for Coromandel Peninsula, Bay of Plenty west of Whakatane, Tairawhiti/Gisborne north of Gisborne City and Tasman west of Motueka till Saturday morning (20 July).
• A strong wind watch is in place for Chatham Islands from 2100 hours Saturday (20 July) to 0900 hours on Sunday (21 July).
• Detailed weather warnings can be accessed at https://www.metservice.com/warnings/home