How to Build a Cloud Triangle

1. How to Build a Cloud Triangle Important: View in “Slide Show” mode to view animations

2. Building the Cloud Triangle Very high, thin and wispy, like a horse tail. Let’s also add some elevation 6000 m So what do these clouds look like? Let’s make some simple sketches. First, let’s draw a triangle. Stratus Good! Now, let’s put these three cloud types at the corners. Okay, what is a common cloud type? Cumulus This one can look like popcorn or cauliflower – sometimes even shapes of animals! 2000 m This one looks and feels like a thick blanket covering the sky. Cirrus

3. Cirrus Cirrus and Stratus can be combined to create Cirrostratus Cirrus and Cumulus can be combined to create Cirrocumulus Cirrostratus Cirrocumulus These clouds are sometimes referred to as fish scales and are sometimes called mackerel sky These clouds look almost like a thin veil in the sky; the Sun or moon often has a circle or halo around it 6000 m Middle-level clouds are called “Alto” Alto Altocumulus Altostratus We can combine these names to identify additional clouds These clouds are a little thicker than cirrocumulus but not as thick or low as stratus; the Sun will appear dull These clouds sometimes form in rows called “cloud streets”; others call them a flock of sheep 2000 m These clouds look like a bunch of cumulus clouds all pushed together into a blanket. Stratocumulus Stratus Cumulus

4. … and if it’s raining… Cirrus Cirrocumulus Cirrostratus 6000 m Altocumulus Altostratus Alto This is usually the slow moving steady rain, often called showers. 2000 m This is usually the fast moving heavy rain, often with thunder and lightening. Stratocumulus Cumulonimbus Nimbostratus Stratus Cumulus

5. … and voilà – the Cloud Triangle! Cirrus Cirrocumulus Cirrostratus 6000 m Altocumulus Altostratus 2000 m Stratocumulus Cumulonimbus Nimbostratus Stratus Cumulus

6. Things to consider when building the Cloud Triangle Cirrus Placement of cloud names 1) Cirrus is a high cloud, therefore should go at the top, or apex, of the triangle. 2) I’ve placed Cumulus to the right and Stratus to the left. Why? • When I add Stratocumulus to the triangle “strato” comes from the left and “cumulus” comes from the right. This will aid in remembering whether it’s stratocumulus or cumulostratus…! 3) When I add Nimbostratus and Cumulonimbus to the triangle “Nimbo/nimbus” is on the outside of the word: Nimbostratus and Cumulonimbus. This will also aid in remembering whether it’s nimbostratus and cumulonimbus or stratonimbus and nimbocumulus…! Cumulonimbus Nimbostratus Strato cumulus Stratus Cumulus