The spectacular meteorological event lasted for around 30 minutes and was witnessed by Andé Luiz Nassif who recorded the natural phenomenon.
Mr Nassif, from Ribeirao Claro, in Brazil’s northerm Parana region, said: “I’ve never seen anything like this. There were some people sitting in a restaurant and they got up to look at the sky”.
Iridescent clouds, or rainbow clouds, are caused by the diffraction of sunlight caused by tiny ice crystals or drops of water suspended in the atmosphere. They often appear on hot and humid days and accompany storms.
Larger ice crystals produce solar or lunar halos, but tiny ice crystals or water droplets cause light to be spread out and create the rainbow-like effect in the clouds.
The usually delicate colours can be in almost random patches or bands at cloud edges.
They are only organised into rings when the droplet size is uniform right across the cloud.
The bands and colours change or come and go as the cloud evolves.
The Atmospheric Optics website says: “Rainbow clouds occur most often in altocumulus, cirrocumulus and especially in lenticular clouds.
“Iridescence is seen mostly when part of a cloud is forming because then all the droplets have a similar history and consequently have a similar size.
“Sometimes iridescence can be seen far from the sun but is most frequent near to it. As for coronas, search safely by hiding the sun behind a building and, even better, also viewing the reflection of the sky in water.
“Very much rarer iridescence is that of nacreous or mother-of-pearl clouds which can glow very brightly and are far higher than ordinary tropospheric clouds.”
Additional reporting by Maria Ortega