Holidaymakers making the most of the warm weather at Kaiteriteri Beach in Tasman in December last year. Photo: RNZ / Samantha Gee
Hot weather is expected to continue on Tuesday, with temperatures set to soar in the coming days and warm nights in many places.
Much of the country basked in sunshine on Monday as many New Zealanders returned to work after the New Year break.
Temperatures in parts of the South Island climbed to more than 30 degrees Celsius on Monday, including Twizel and Alexandra.
Hawke's Bay is expected to be the hottest area today with Hastings forecast to reach 30 degrees.
MetService says high pressure will continue to grip the country later this week with parts of Canterbury forecast to reach 30 degrees on Thursday, with Ashburton tipped to reach 33 degrees that day.
For most of the country, MetService is forecasting a hot and dry rest of the week, with warm muggy nights and not much rain.
"A very settled looking week this week and those temperatures set to climb" - John Law
MetService meteorologist John Law said it was a settled looking week with high temperatures, particularly on the eastern side of the South Island.
"I think for places like Christchurch and Ashburton for Thursday I think we could find those highs back to around 32 or even 33 degrees Celsius."
Temperatures could also reach 30 degrees in central and eastern parts of the North Island, he said.
Te Whatu Ora is urging Cantabrians to keep cool and hydrated as the mercury climbs this week.
Canterbury's medical officer of health Matt Reid said a run of hot weather could prove fatal if people were not careful.
The elderly, infants, pregnant women and those suffering from chronic, acute and severe illness should be particularly cautious, he said.
Everyone should avoid going outside during the hottest part of the day, stay hydrated and wear lightweight, loose-fitting and light-coloured clothing, Dr Reid said.
Law said the forecast was for it to be warm nearly everywhere, with the exception being far southern parts of New Zealand which may get more cloud and wetter weather.
The hot days were likely to lead to "warm sticky muggy nights", he said.
"So if we look at some of those temperatures for tonight [Tuesday], places like Napier and Hawke's Bay lows of 18 degrees Celsius - that's a pretty decent daytime temperature I would say, so a really warm night."
The warm weather will continue in Napier where overnight lows of 18 degrees are forecast for the next three days, he said.
"It's that continuation of warmth so well worth trying to keep those bedrooms cool and perhaps keeping some nice cool sheets out for the evenings."
The high pressure is expected to stay in place across the country through the week and into the weekend, he said.
"We have got some cloudy conditions across the far southern parts of New Zealand and as we head towards say Thursday, Friday we'll find some wetter weather pushing back on towards that western coast and down the far south as well.
"So it's not brilliantly dry everywhere, but if you're on that eastern side of the North Island, if you're on most of the North Island I think we've got some pretty dry weather - an odd shower here or there."
Firefighters fighting a series of fires along the railway line near Kirwee, west of Christchurch, on Sunday evening. Photo: RNZ/ Adam Burns
Warmer weather leads to increased fire risk
A restricted fire season has been declared for the Canterbury district as fire danger increases across the region.
Fire crews have responded to several scrub fires over the past two days, including two in Canterbury on Sunday and another in Wairarapa on Monday night.
A mix of hot, dry and windy conditions around the country is being described as highly conducive for fast-moving fires.
Fire and Emergency said Sunday's fires along the Darfield railway line provided a timely reminder that it only took a spark to start a wildfire.
Canterbury district commander Dave Stackhouse said with warm weather forecast to continue this week, the fire danger in the district would only increase.
The restricted fire season - which meant people needed a permit to light an open fire - would come into effect at 8am on Wednesday.
Fire and Emergency is urging property owners to have emergency plans in place as the country's hot and dry weather heightens fire risk in some parts.
Fire and Emergency wildfire specialist Rachel Thorp said people needed to be prepared.
"Our sort of message is 'don't wait until there's smoke in the air to prepare'. So get ready now, prepare your property keep your grass short around your home and buildings and things like gutters and that and also have a home emergency plan."
Thorp suggested outdoor activities like grinding and lawn-mowing should be done either early in the morning or later in the evening.
Anyone wanting to check whether they are able to light a fire can visit the checkitsalright website.
Meanwhile, a farmer in Canterbury's Mackenzie district said he was on high alert amid a heightened fire risk in the area.
A complete fire ban is in place for the entire Mackenzie Basin, with hot dry and windy conditions expected for the rest of the week.
Several crews managed to contain a fire that covered a kilometre near Lake Ohau on Sunday, prompting further warnings about the volatile wildfire conditions.
Lake Ohau station manager Tom Moore said with a high volume of holidaymakers, people needed to be extra careful.
"We've got a lot people who want access to the station because we've got DOC land on the other side of us and they want access for tramping and stuff.
"I'm just about at the stage where I'm going to have to stop people going because it's just too dangerous."
Moore said his station experienced its driest November and December in more than 70 years.