From Nasa’s Terra satellite, an image of fallstreak holes in clouds over the southern United States

© NAS

High above the clouds. What happened to these clouds?

Today is World Meteorological Day, so we’re high up in the atmosphere, above the clouds, for a satellite view of fallstreak holes – gaps in the clouds that are also known as hole-punch clouds. The holes form when supercooled water droplets suddenly freeze – often when a plane flies through the cloud – and then fall, leaving an opening in the formation. Scientists are still gaining new insights on how fallstreak holes form and behave.