By Tanda Gmiter | email@example.com
The Arctic cold snap that is pushing through the Great Lakes today and tomorrow might make being outside feel brutally frigid, but it’s doing some really lovely things to the clouds overhead.
This freezing air pouring over our warmer Great Lakes is creating “cloud streets” – nice little organized rolls of clouds that stream parallel to the wind direction. On satellite images, it makes the weather conditions look a lot prettier than they feel.
An NOAA satellite image capturing the cloud conditions over our biggest Great Lake was shared today by the Cooperative Institute for Meteorological Satellite Studies (CIMSS) at the University of Wisconsin-Madison.
“Moonlit cloud streets over Lake Superior last night flowing perfectly aligned and parallel to the cold north wind heralded the arctic blast currently descending upon the Great Lakes Region,” CIMSS meteorologists wrote. “Temperatures will be below normal to wrap up the work week and wind chills will be brutal.”
According to our friends at NASA, cloud streets are formed when thermals – or columns of warmer air – rise up through the atmosphere and lift the heat away from the surface of a sea – or a Great Lake.
“The moist air rises until it hits a warmer air layer … that acts like a lid. (This) inversion causes the rising thermals to roll over on themselves, forming parallel cylinders of rotating air. On the upward side of the cylinders (rising air), water vapor condenses and forms clouds. Along the downward side (descending air), skies remain clear,” according to a NASA blog.
“Cloud streets are not limited to the skies over the open ocean. For example, during cold spells you can frequently see them streaming over the Great Lakes.
As I read this it, I thought the phenomenon was interesting and the phrasing of a quote was poetic. I arranged it into a tanka:
Moonlit cloud streets o’er
Great Lake, perfectly aligned
parallel north wind
Herald arctic blast’s descent
Upon the Great Lakes Region
Then I thought to write my own impression:
Moondance on cloud streets
Crystalline gowns swirl breaths’ mists
To cat’s fiddled tune.