I’ve lived in Hawaii for such a long time that I’ve nearly forgotten what different varieties of clouds look like on the mainland, until an Aussie designer friend of mine forwarded me this link this evening. The images are amazing, and made me nostalgic, and anxious to return.

Mammatus are pouch-like cloud structures and a rare example of clouds in sinking air. Sometimes very ominous in appearance, mammatus clouds are harmless and do not mean that a tornado is about to form - a commonly held misconception. In fact, mammatus are usually seen after the worst of a thunderstorm has passed.