Some of you may be aware, I'm always saying 'Look up it's free'. During these lock-down times it's something we can all do from our own back gardens or windows and today it certainly paid off.
The sky today (Wednesday) has been brushed with a wonderful display of cirrus clouds, mostly cirrus uncinus.
What are cirrus clouds?Cirrus clouds are short, detached, hair-like clouds found at high altitudes. These delicate clouds are wispy, with a silky sheen, or look like tufts of hair. In the daytime, they are whiter than any other cloud in the sky. While the Sun is setting or rising, they may take on the colours of the sunset.
Cirrus clouds form from the ascent of dry air, making the small quantity of invisible water vapour in the air undergo deposition into ice (to change from a gas directly into a solid). Cirrus is made up completely of ice crystals, which provides their white colour and form in a wide range of shapes and sizes.
What weather is associated with cirrus clouds?They often form in advance of a warm front, where the air masses meet at high levels, indicating a change in the weather is on the way.
Technically these clouds can produce precipitation but it never reaches the ground. Instead, it re-evaporates below the cloud.
Cirrus clouds have five defined 'species';
Cirrus fibratus - Thin and fibrous, cirrus fibratus are often aligned with the high altitude wind direction, making for white parallel stripes which streak across the sky. These are the most common type of cirrus cloud
Cirrus uncinus - With its trademark hook shape, cirrus uncinus is famous for looking like a horse's tail. These wispy streaks of cirrus cannot be seen without a characteristic 'flick' at the end of its tail
Cirrus spissatus - These clouds sit right at the top of the troposphere. A thick, dense cirrus layer that dominates much of the sky above, often formed by passing warm fronts or the remnants of a cumulo-nimbus
Cirrus floccus - Ragged cirrus patches which are much larger than cirrocumulus floccus. These have a more cotton wool-like appearance than the rest of the cirrus family
Cirrus castellanus - More vertically developed than cirrus floccus, cirrus castellanus have turret-like tops and are taller than they are wide.
The Cirrus clouds we saw today were mostly cirrus uncinus and I think you'll agree they are quite delicate and beautiful.
They appear to be static in the sky but if you take to a deck-chair (with or without a G&T) and watch them closely you can see that they are in constant motion describing wonderful contortions in the sky rather like an old-fashioned kaleidoscope.
Will they be there again tomorrow? It's more than likely but remember it always pays to #Lookupitsfree.