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July 21, 2025
A cloud formation that resembles a DNA double helix is likely a Kelvin-Helmholtz (Fluctus) cloud or a double helix cloud. These formations are not a specific type of cloud, per se, but rather a visual phenomenon resulting from the interaction of air layers moving at different speeds and densities. This results in air flows that tend to have a distinct serpentine motion. This rare sighting was spotted over Auckland, New Zealand.
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