Nor'west arch

Föhn cloud formation in New Zealand

The Nor'west arch is a weather pattern peculiar to the east coast of New Zealand's South Island. For this reason, it is also often referred to as the Canterbury arch, although it is visible in both Otago and Marlborough as well as in the Canterbury Region. It is shown in an apparent arch of high white cloud in an otherwise clear blue sky over the Southern Alps, and is accompanied by a strong hot northwesterly or northerly wind simply known as The Nor'wester.

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