Auckland is expected to have clear skies with light winds over the harbour, and cool evening temperatures around 11 or 12C, with Wellington temperatures just a bit cooler at around 10C at show time.
Conditions for the Wellington Marathon on Sunday should see a mix of fine and cloudy periods, northerly winds and a high around 13C.
Wrap up warm if you're heading to the Super Rugby game between the Crusaders and Hurricanes on Saturday, where temperatures are expected to dip to 6C.
The ridge will also continue to bring frost and fog to many places overnight, especially in sheltered valleys and basins.
Forecast
Northland, Auckland, Waikato and Bay Of Plenty
Sunny for most, a morning mist or fog patch about the Waikato. Some cloud and the risk of a shower at times for Great Barrier Island and about Northland, especially in the east. Southeasterly winds.
Highs: 12-15C
Western North Island (including Central North Island)
Sunny with light winds, could be morning mist or fog patches about inland areas.
Highs: 10-13C
Eastern North Island
Sunny with light winds.
Highs: 10-13C
Wellington
Mostly sunny, light winds tending northerly.
High: 12C
Marlborough and Nelson
Sunny with light winds.
Highs: 11-13C
Canterbury
Sunny, light winds tending northeast in the afternoon.
Highs: 10-12C
West Coast
Sunny with light winds, some cloud about southern Fiordland may produce a light shower or two.
Highs: 11-12C
Southland and Otago
Mostly sunny, there may be some cloud at times right on Southland's coastal fringe. West to northwesterly winds.
Highs: 8-12C