The Mysterious Disappearing Rain
The scattered thunderstorms of this week created several opportunities to witness a weather phenomenon that you may have seen a number of times, but didn’t quite know what to call it.
In the image above, the setting sun brought a beautiful glow to the clouds and helped to illuminate what appears to be rain falling from the cloud – but where did the rain go? It seems to disappear before it reaches the ground. You can see a similar situation with the rain that is falling out of the bottom of the remnants of the thunderstorm in the image below. Just 15 minutes earlier, this was a vigorous storm, but as the storm weakened, it eroded from the bottom up leaving a still menacing looking anvil top, and shafts of virga. Virga (Latin for “rod”) is precipitation that falls from a cloud, but that changes into water vapor before it reaches the ground. This occurs when the precipitation, which can be liquid as rain, or frozen as snow or ice particles, passes through a layer of dry air.
Virga is a fairly common occurrence in Western North Carolina, and is very common in the Western U.S. where the climate is much more arid. So, the next time you see it, you’ll know what to call it, impressing your friends and family with your geekiness.
Learn more about climate fun facts here.
July 26, 2012