Aucklanders now know what Prince meant when he wrote Purple Rain as they were treated to a striking lavender-coloured sky on Thursday.
MetService meteorologist Tom Bell said his educated guess would be that the uniquely coloured sky was "probably something to do with the scattering of the light from rain droplets".
Different wave lengths of light which produce different colours got scattered when they interacted with rain drops, he said.
• Watch: Metservice weather forecast for NZ - January 18th-20th
The purple sky came as a pleasant surprise to Aucklanders following a day of wet weather.
Despite the rain, the city experienced a balmy high of 25 degrees amidst outbreaks of rain with heavy falls and brisk north easterlies.
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