Thanks to all of you that sent it pictures of the neat clouds just ahead of the rain today. This one is from Larry Cloud…
They are named ASPERITAS clouds (formerly Undulatus Asperatus). The name comes from the Latin word for “roughness” or “harshness”. In fact the name just changed last year as the World Meteorological Organization decided it was time to give them an upgrade with this very detailed explanation:
“Well-defined, wave-like structures in the underside of the cloud; more chaotic and with less horizontal organization than the variety undulatus. Asperitas is characterized by localized waves in the cloud base, either smooth or dappled with smaller features, sometimes descending into sharp points, as if viewing a roughened sea surface from below. Varying levels of illumination and thickness of the cloud can lead to dramatic visual effects”
There you have it. I’ve seen these maybe once/twice a year in our area, which is pretty rare considering how many clouds we get in 365 days!
Here are some more pics from viewers…enjoy a little slideshow!
Chief Meteorologist Mark Nelsen