Cirrus Uncinus is a dramatic and distinctive cloud type. They are a type of high level cloud. This means that they form at altitudes of over roughly 5000 meters.
I photographed these cirrus Uncinus clouds hovering over Townsville, Australia. Townsville is a city in north east Queensland. I photographed these clouds using my mobile phone!
The temperature at which these clouds form can be extremely cold. It can get down to as low as -40 to -50 degrees centigrade. Keep an eye out for these clouds along certain types of weather fronts. Look out for them along occluded fronts and warm fronts but of course there are usually exceptions to the rule, I keep a camera with me at all times so when interesting clouds appear I can photograph them.