Warning for vulnerable as Canterbury prepares to sizzle

Te Whatu Ora is urging Cantabrians to keep cool and hydrated during what looks set to be a stretch of scorching temperatures hitting the region this week.

Hot weather is forecast for Christchurch, with temperatures predicted to get to a maximum of 30C on Thursday and 29C on Friday.

Sticky weather on the way

Later this week a northerly wind flow sets up camp across the country.

This air from the north will be notably humid for many places and temperatures around Otago, Southland and Canterbury could be pushing towards 30°C. pic.twitter.com/RcSgpykSod

— MetService (@MetService) January 24, 2023

Canterbury medical officer of health Ramon Pink said overheating was a condition that could prove fatal.

"It's especially important to stay out of the sun where possible, avoid extreme physical exertion and ensure pets and people are not left alone in stationary cars.

"While we are all vulnerable to hot temperatures, some people are particularly at risk. This includes the elderly, infants and children, women who are pregnant or people suffering from chronic, acute and severe illness," he said.

Dr Pink also advised people to drink plenty of water and reapply sunscreen every two hours if outside.

"As well as being sunsmart (slip, slop, slap and wrap) if you have to go outside, everyone is advised to keep their houses cool by closing curtains on windows getting direct sun, opening windows to get a breeze if it's cooler out than in, and consider using the cool cycle on heat pumps," he said.

Canterbury will move into a restricted fire season on Thursday due to an increase risk of wildfires, which means a permit will be required for all outdoor fires.

The shift will cover from the Rakaia River north, including the hill and high country, the foothills and Canterbury Plains, Banks Peninsula and the Port Hills, Christchurch city and the Kaikōura Plains.

Fire and Emergency Canterbury community risk manager Dean Harker said hot weather mixed with wind and dry vegetation was a real concern.

He advised people to go to checkitsalright website to get an idea of the conditions and whether it was safe to light a fire, even if they had a permit.

"We actually had a fire in North Canterbury yesterday that was controlled but, with the conditions, the fire got out of hand which then required resources to go and deal with it," Harker told Morning Report.

"Anything can start a fire, just a [lawnmower] blade hitting a rock or something like that. So we urge people to not do that in the extreme heat of the day, look for other times during the day to do that, but be very mindful that if a spark ignites something, quite quickly the fire can get out of hand."

The hot weather forecast is set to drag into next week, but the restrictions would be reviewed daily, he said.

"Even with a little bit of rain at the moment, it's not really going to make a difference to that vegetation just because it is so dry."

Warm temperatures to last several days

MetService said the South Island was unlikely to have a respite from hot, dry conditions until next week.

Communications meteorologist Lewis Ferris said a low pressure system sitting to the north-west of the country was dragging down sub-tropical air, bringing warm, humid air to the South Island, and significant rainfall to parts of the North Island.

A bit of rain has been forecast to move north on Friday, but it was unlikely to make a difference, he said.

"Even as we head into next week, it's really looking to be maybe the second half of next week that we see the best potential for some more widespread rain," Ferris said.

"So if you're getting a bit dry in your water tank, there might be a little respite on the way."

If Christchurch got as warm as predicted it would still be well off a record.

"That is about seven degrees above what we would expect for an average January day but we're not getting close to record territory yet. You'd need to get up around that 37 degree mark to get into those top temperatures for the Christchurch station in January."

Overnight temperatures were expected to stay warm, Ferris said.

The list of all the restricted and prohibited fire seasons in the South Island

South Island areas with prohibited fire season - a prohibited fire season means a total ban on outdoor fires, and all previously granted fire permits are suspended.

West Coast Inland Buller - prohibited fire season

Otago

Lakes and Central Zones - prohibited fire season

Otago's Clutha zone - prohibited fire season

Upper Waitaki - prohibited fire season

Southland

Coastal Southland - prohibited fire season

Stewart Island - prohibited fire season

All public conservation land - prohibited fire season

South Island areas with restricted fire season - a restricted season means people will need a permit to light a fire in the open air.

Marlborough - restricted fire season

Nelson and Tasman - permanently restricted fire season

West Coast

Buller and Grey Districts - restricted fire season (except Inland Buller, which is in a prohibited fire season)

All public conservation land - permanently restricted fire season

Westland District - restricted fire season

Grey District - all fire permits suspended

Canterbury - restricted fire season (from the Rakaia River north, including the hill and high country, the foothills and Canterbury Plains, Banks Peninsula and the Port Hills, Christchurch city and the Kaikōura Plains)

South Canterbury

Ashburton High Country, Mackenzie Basin High Country and Hakataramea Valley - restricted fire season

Geraldine Forest Zone, Waimate Forest Zone - permanently restricted fire season

All public conservation land - permanently restricted fire season

Mackenzie Basin - fireworks ban

Otago - Dunedin, Strath Taieri, and Coastal Waitaki - restricted fire season.

Southland - restricted fire season (except for Coastal Southland and all public conservation land, including Stewart Island, which are in a prohibited fire season)