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Like flying saucers, lenticular clouds hover over Charlottesville, Va. this morning

Lenticular clouds over Charlottesville, March 10, 2014. (Travis Koshko)

No, they weren’t UFOs floating over the central Virginia skies, but super rare lenticular clouds – more common in the mountain West.

Meteorologist Travis Koshko shared the above shot grabbed from Charlottesville’s airport not long after sunrise – captured by a webcam in his station’s (CBS19) “Skyline network“.

Here’s another shot from reader @davidbarney on Twiter:

And one more from reader @lxkatz:

How does these other worldly clouds form?  Here’s a short description from a previous CWG blog post on “weird clouds”:

When stable, moist air streams over a mountain and is heated,  it condenses into this lens-shaped cloud.
The wind that brings the air over the mountain then cools and sinks in a wave pattern, which can lead to a line of lenticular clouds extending away from the mountain that build on the crests of the airwave and diminish at the troughs.
These clouds can also stack vertically when there is a layer of dry air between two layers of moist air moving in the same direction over a mountain.

The National Weather Service forecast office in Sterling posted this image and narrative on Facebook, describing the favorable environment for these clouds:

This morning, a phenomena known as “wave clouds” are evident on satellite imagery across Virginia and Maryland. The base of these clouds are approx 10,000 feet and are quite thick east of the Blue Ridge (approx position shown by red lines in image/inset). These clouds form as upper level moist winds blow perpendicular to mountain ridges. The larger image shows a GOES visible image from 1045 AM EDT. The inset lower right shows an 9 hr forecast valid at 11AM EDT from the HRRR-High Resolution Rapid Refresh 3km model of outgoing longwave radiation flux (watts/meter^2). This field is often a good way to help predict wave clouds.