Overheating is a much bigger threat for Rotorua's babies and toddlers, than for teens and adults.
Not only do they struggle to communicate, but infants, particularly those under 12 weeks, also struggle to regulate their temperature.
Rotorua mother Karyn Kerrison has been carefully managing the heatwave with her 10-week-old son Jasper.
"When we leave the house we either go to places with big shady trees, or spots in town with air conditioning, like the library."
She said Jasper had been more thirsty than usual, so she was drinking more too.
"It has been a little bit harder for him to get to sleep too. His room is upstairs and it gets extra hot up there, so he naps downstairs or under shade until his room is cool enough in the evening."
Alice Waitoa takes antenatal classes and car seat clinics at the Rotorua Parents Centre.
She said Monday night's classstruggled in the heat and ate ice blocks.
"The expectant mothers have been having to drink more, put their feet in icy water, they've been swimming lots, and pumping the air conditioning."
She urged parents to take extreme caution with children in cars because temperatures inside stationary vehicles can be 30C to 40C warmer than outside.
"A sheet or a towel over the car seat can also prevent buckles from heating up and burning kids. Also, it's best to keep the car parked in the shade between drives, and to turn it on to get the air conditioning running before you hop in."
She said children should never be left alone in cars, regardless of whether a window was down, or if the parent was only gone for a few minutes.
Breastfeeding in hot weather
• Breastfeed on cue, according to demand
• Babies under 6 months do not need additional water
• The composition of breast milk will naturally have higher water content in hot weather to meet babies' needs
• A flannel or towel draped between a baby's skin and mother's can increase comfort
• Mothers need to drink more fluids to meet extra breastfeeding needs
• Mothers are legally entitled to breastfeed in public places, including swimming pools
Source: La Leche League New Zealand