Kiwis with asthma and other respiratory conditions have been warned smoke from the Australian bush fires could impact their breathing.
Smoke had been drifting over the Tasman Sea for several days, with noticeable effects across the country.
And if the smoke reached low air levels, those with asthma, COPD and other respiratory conditions could have trouble breathing.
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Asthma and Respiratory Foundation chief executive Letitia Harding said there hadn't been any official reports of increased respiratory problems yet, however, people with respiratory conditions should always be mindful of potential risks.
"If you have a respiratory condition, you should ensure that you keep your medication with you at all times," Harding said.
"It's also a good time to remember that medication does expire, and so you should ensure that your inhalers are up to date in case you need them."
Smoke could irritate and trigger worsening of respiratory illnesses with children and the elderly among those most at risk of unexpected flare-ups.
The best advice Harding could offer was to tell people with illnesses to always keep their reliever medication on hand.
"If you are experiencing worsening of your respiratory condition, or believe you may be developing symptoms, contact your GP as soon as possible to discuss your options."
On Sunday, an orange haze caused by smoke from the Australian bush fires blanketed much of New Zealand's North Island.
Scores of people were gobsmacked at the sepia-like effect the smoke had on their surroundings, with many people calling 111 for help.
Police were inundated with so many phone calls they had to remind the public what constituted an emergency.