Last Thursday, Brian Tuttle spotted some very interesting looking clouds over Cole Harbour, N.S. He took a few photos and submitted them, wondering if they had a name.
These delicate waves that look like strokes from a painter’s brush are known as Cirrus Undulates.
Let’s start with cirrus. Cirrus is a Latin word meaning a ringlet or curling lock of hair.
Cirrus clouds are the most common of the high clouds; they form between 5,000 and 14,000 metres above the ground. They are thin, wispy clouds made of ice and from where we stand they appear white or light grey in colour.
Brian’s clouds were cirrus clouds but they were exhibiting a pattern – a wave, or undulation. This wave is created when warm and cold air meet or when dry air comes up again a dry air mass. All in all, cirrus undulatus clouds indicate there are rising masses of warm air meeting with cool, high-altitude air.
They are most common when surface temperatures are relatively cool or in the early stages when the weather starts to get destabilized. These clouds are most often observed in the morning. Brian spotted these in the morning, as a moist air mass was pushing in ahead of the rain that started early Friday morning.
By watching the movement of cirrus clouds you can tell from which direction weather is approaching. When you see cirrus clouds, it usually indicates a change in the weather will occur within 24 hours; it sure did.
Thank you for keeping an eye in the sky Brian.
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Cindy Day is the chief meteorologist for SaltWire Network.
