A scorcher of a day across much of the country has prompted a health warning.
Hot air is blowing across from Australia, where it's already caused havoc. Out-of-control bush fires are currently tearing through Tasmania - and there are fears we could be next.
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Temperatures are expected to push right into the high 30degCs this week, creating an extreme fire danger and causing concerns for people's wellbeing.
Cromwell reached of 35degC on Sunday, which NIWA said in a tweet was the highest temperature recorded this summer.
MetService recorded a temperature of 35.3degC at Woodbourne near Blenhiem, the highest in the country.
Hawke's Bay and Blenheim are both expected to reach 35degC on Monday.
Other areas, including the Bay of Plenty, Waikato, parts of Northland, Nelson and Queenstown will hit the high 20s.
Canterbury medical officer of health Dr Alistair Humphrey told Newshub extreme heat can affect blood pressure and hydration.
"Stay out of the sun, particularly if you are elderly or if you have young children, keep them out of the sun," he said.
Dr Humphrey warned parents in the affected areas need to ensure their children are protected from the sun, especially as schools are back in session.
"Make sure all your children are properly covered so they don't get burned, that they have a hat with a proper brim, that they have access to water at all times."
The hot temperatures are expected to stick around until the end of this week.
Expected highs for Monday:
Hawke's Bay: 35degC