Pack your sunscreen - it's Auckland Anniversary weekend and the weather is "certainly coming to the party", MetService says.
Warm summer temperatures are expected for the weekend across the country, with most places hitting 30C on Sunday.
A ridge of high pressure settles over New Zealand today, bringing fine weather for most.
But MetService is forecasting a trough lingering over the upper North Island on Friday afternoon could trigger isolated showers from Bay of Plenty to Northland.
Sports fans and those heading to Auckland Anniversary weekend events should pack their sunscreen.
Fine weather is expected for both the Black Clash cricket at Christchurch's Hagley Oval on Friday and the Black Caps ODI with India on Saturday in Tauranga.
Those attending the range of events happening across the region on Auckland Anniversary Day, including the Laneway Festival, will enjoy a warm high of 27C that afternoon.
"The weather is certainly coming to the party," MetService said.
But the story is not so flash for the South Island, where some areas could be hit with heavy rain and gales tomorrow.
"Strong, warm northwesterlies once again build over the South Island during Saturday as the ridge stalls over the upper North Island," MetService Meteorologist Rob Kerr said.
"So areas of heavy rain are forecast for the West Coast of the South Island, with gales affecting eastern parts of the South Island and lower North Island."
Kerr said the warm air blown in by northwesterlies on Sunday will send temperatures soaring, with many places expected to break the 30C during the afternoon.
"The high humidity is likely to mean some uncomfortable nights as we start the working week, with minimum temperatures of 20C for many places."
Friday weather:
Whangārei: A few showers from late morning as southwesterlies turn easterly. High 25C Low 16C
Auckland: Isolated showers. Southwesterlies turn easterly for a time morning and afternoon. High 24C Low 16C
Tauranga: Cloud morning and evening, but fine in between. Easterly breezes.
High 23C Low 15C
Whanganui: Fine. Light winds, then westerlies developing afternoon. High 23C Low 13C
Napier: Cloudy periods. Northeast developing afternoon. High 23C Low 14C
Wellington: Fine. Light winds, then northerlies developing in the evening. High 21C Low 15C
Christchurch: Fine. Northeast breezes developing afternoon. High 21C Low 12C
Dunedin: Cloudy periods, and chance showers from afternoon. Southwesterly dying out. High 19C Low 13C
Source: MetService
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