It's a scorching day around the country with temperatures set to hit 32C and a heat alert issued for Blenheim.

Taumarunui, Lower Hutt and Central Otago are set to be the hottest spots, but nowhere will escape the heat.

At midday MetService said Lower Hutt was leading the pack on 31C, followed by Invercargill on 28.5C and Blenheim on 28.3C.

MetService meteorologist Mmathapelo Makgabutlane said the hot weather may be great for those on their summer holiday, but people need to remain sun-smart given the sweltering conditions.

"Just a reminder that these temperatures are lovely for most people but there will be people who will be a little bit more vulnerable to these warmer temperatures.

"I think the blanket message is remember to stay hydrated, be sun-smart, and take care of those who might be a little more vulnerable in these warm temperatures."

The Ministry of Health has advice for those wanting to stay cool and healthy on its website, including to drink plenty of water and cut down on alcohol.

It advises people to stay out of the sun – either by finding shade or staying indoors – and try to exercise outside in the early morning or late evening when the sun isn't so harsh.

If you are outside, it recommends slipping on some clothing, slopping on some sunscreen, slapping on a wide-brimmed hat, and wrapping some sunglasses over your eyes.

Keep your house cool by opening windows to capture any breeze there is, or turn on the air conditioning. Close curtains or blinds to keep the sun out. And don't forget to check on your neighbours, especially the elderly.

Both humans and animals need to stay well hydrated in the heat. Photo / 123RF

There is also a reminder about children, who find it more difficult to cope in the heat, as do animals, and the advice is to never leave a child or pet unattended in a parked car.

The SPCA says it takes only minutes for a pet left in a vehicle on a warm day to succumb to heatstroke and suffocation.

"On a 30C day, temperatures in a car parked in the shade with the windows down can exceed 39C in less than five minutes, and in 30 minutes it can go up to a deadly 49C. This can occur even in the shade and if you have left the windows open.'

Children can find it more difficult to cope in the heat. Photo / 123RF

The animal welfare agency says people also need to keep a particularly close eye on pets who are older, overweight, flat-faced, or have thick fur, as they may struggle more in the heat.

"Bulldogs and pugs are more susceptible to heat stroke since they cannot breathe or pant as effectively as dogs with longer noses."

When it comes to taking your dog for a walk, do it in the morning or evening, as the sun is at its fiercest between 10am and 4pm. If you're headed for the beach, check the sand isn't too hot, as it can burn the pads of your pet's paws and leave them "sore, blistered and red".

And it's not just humans who can get sunburnt - pets that are fair-skinned or light-haired are particularly susceptible to the sun's harsh rays.

"Skin cancer can occur commonly in dogs and cats, so your pet needs a pet-friendly sunblock applied every three to four hours to areas of their body that have no, or little, hair-covered spots."

Take your dog for a walk in the morning or evening, when the sun and heat isn't so harsh. Photo / 123RF

For smaller animals like rabbits and guinea pigs, make sure their enclosure is positioned in a shady spot. And sheep, horses and cows must have access to shade.

And just like us, all animals need to keep hydrated.

"Having fresh water available for your pet is essential all year-round, but even more important when it's hot outside."