Last evening a line of intense thunderstorms accompanied by high winds (and even a tornado in Huron County) rolled across Michigan toppling trees and knocking out power to tens of thousands. I was awoken from my pre-work nap by my alarm clock as I had slept through the whole storm.
Per our evening ritual, I took the dog out to empty his accumulated liquids and solids before he turned in for the night. When we headed back toward the house, I looked up and saw that mammatus clouds had formed in the wake of the storms.
Mammatus aka mammatocumulus (or mammary clouds) are named for their sac-like structures that are said to resemble a cow's utter or human equivalent. Most clouds form when warm humid air rises and condenses in cooler air. These clouds on the other hand, develop when cool moist air containing large drops or even ice crystals descends into drier air. The mammatus phenomena can be a long lasting feature, as it may take a while for the large drops to evaporate.
The common misconception that I had heard growing up, was that they are associated with tornadic activity. But only times I have seen them were after a severe storm had passed and the dry zone into which they formed had sucked the energy out of the atmosphere.
|Taken from my driveway|
editor's note: we've been trying to keep this blog focused on birds, so nerdy sky stuff pertaining to weather and astronomy has been posted to another site Mostly Nerd (but not always) , It's not getting much activity so either people haven't found it or they aren't interested. If under the radar music is your thing there is another site in the Mostly (but not Always) franchise called Mostly Heard (but not Always)