Summer humidity, heat set to rise: Where temperatures could hit mid-30s this week

Temperatures could nudge toward the mid-30s in parts of New Zealand later this week - but a meteorologist warns the heat’s likely to come with sticky humidity.

MetService is forecasting warm, sunny weather for most regions throughout the week, courtesy of a broad ridge of high pressure draped over the country.

After temperatures hit 31C in Alexandra on Monday afternoon - and nearly hit 30C in Masterton - the mercury could rise even higher on Thursday.

“Temperatures are forecast to crack 30C for most of Canterbury on Thursday, reaching 33C in Ashburton,” MetService meteorologist Ngaire Wotherspoon said.

The scorching outlook came with a northwesterly flow across the South Island, which was expected to become strong on Wednesday night and bring hot, dry winds to eastern and inland areas.

In the North Island, Wotherspoon said a few showers could still appear in the afternoons and evenings this week as daytime heat helped cloud build, “though you would be unlucky to encounter one”.

Temperatures in Auckland were forecast to reach 27C on Friday and over the weekend, while Wednesday could bring a maximum of 28C for Hamilton.

Elsewhere, MetService was forecasting highs of 26C in Tauranga and Whangārei on Friday and Saturday, while Sunday’s temperatures could reach 33C in Hastings and 32C in Napier.

“Thursday, Saturday and Sunday certainly look to be the hottest days, with readings that could push toward 35C in some places, before a cold front moves northward,” Niwa forecaster Ben Noll said.

“But humidity is also going to be a factor for much of the country, especially toward next weekend - it’s going to be pretty impressive.”

Noll said a southerly front forecast to follow would bring a brief reprieve from the heat.

“We’ll be back in the warmth and humidity not too long after.”

While Niwa was picking higher chances of rain later this month, its just-issued outlook for the next three months predicted near-normal rainfall in the North Island’s north and east and west of the South Island and near or below normal levels elsewhere.

Temperatures were likely to be above average in the west of the South Island and very likely to be above average elsewhere, owing to more frequent northwesterly winds.

Jamie Morton is a specialist in science and environmental reporting. He joined the Herald in 2011 and writes about everything from conservation and climate change to natural hazards and new technology.