Question: I often hear the expression “every cloud has a silver lining,” and have seen the effect myself, but not on every cloud. What causes this? — CM, New River, AZ
Answer: Those “silver linings” are the same stuff the rest of the cloud is made from; tiny droplets of water that condensed on particles of dust or smog in the air. All clouds are formed in this way. Of course, clouds caused by dust storms or forest fires are whole ‘nuther thing. What we’re talking about here are normal water clouds.
The photo above was taken during this year’s monsoon season, when water clouds were plentiful. You can tell by the brightness of the sky that the Sun is right behind that cloud. When the angles are just right, light from the Sun will reflect from the edges on the cloud and scatter forward to the lucky observer. The dark part of the cloud is thicker, and lies in its own shadow. The silver lining, however, is lit by the full brightness of the Sun.
So the old adage “every cloud has a silver lining” is unfortunately just not true — not in life or in the sky. If the Sun isn’t not behind a cloud, you can’t get this effect. And the lining is not always “silver.” When combined with the colors of a spectacular desert sunset, the lining can be yellow, orange, red, or even violet. For a great photo of a “gold lining” see my column Why Some Sunsets are Not Red.