After a sizzling start to summer, MetService is forecasting a brief reprieve from the heat on Friday and Saturday.

However, by Sunday, northwesterlies look set to blast over the country, ushering in a large frontal weather system that will bring heavy rain to the West Coast of the South Island.

This week marked the first wave of MetService Heat Alerts for the season, issued for eastern parts of the country due to soaring daytime temperatures and balmy overnight conditions.

Today (Thursday), these alerts remain in place for Blenheim, Napier, Hastings, and Gisborne, with maximum temperatures again climbing into the 30s.

Relief is in sight as a cooler southwesterly flow spreads across Aotearoa New Zealand on Friday, bringing temperatures back to average for December.

MetService meteorologist Mmathapelo Makgabutlane said, “This respite will be welcome news for those who’ve struggled through the muggy nights. However, by Sunday, the heat looks set to ramp up again in Hawke’s Bay.”

Brisk winds prevail over much of the South Island today, with a Strong Wind Watch in place for Dunedin, Clutha, and southern Southland, including Stewart Island, until 8pm.

Southern Hawke’s Bay and the Tararua District are also under a Strong Wind Watch until 5pm.

Friday and Saturday bring plenty of sunny skies in between cloudier periods.

A few showers also pop up for some areas, mainly inland South Island on Friday – with a possible thunderstorm for Otago and the Mackenzie District – and the odd shower for both main islands on Saturday. 

Sunday brings a dramatic shift as gusty northwesterlies sweep across the South Island and lower North Island.

Makgabutlane said, “Gusty northwesterlies will be felt across the South Island and lower North Island, with severe gales possible in exposed areas.

“Heavy rain is also expected along the western South Island. Keep an eye on www.metservice.com for updates and any severe weather information.”

For cricket fans in Wellington, the Black Caps’ test match begins with a refreshing southerly breeze, though northerlies will strengthen by Sunday.

Football enthusiasts in Auckland can expect dry conditions for the Auckland-Wellington clash on Saturday evening.