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Pic of the week: Pancakes anyone? Lenticular clouds hover over Mount Rainier

A lenticular cloud over Mount Rainier, Wash. (Bryan Best)

It’s not every day the National Weather Service offices forecast a high likelihood of lenticular clouds, but that’s exactly what NWS Seattle did last weekend:

And they were right! By that evening dozens of pictures of lenticular clouds that were spotted over the Pacific Northwest posted on Twitter.

Lenticular clouds, or altocumulus standing lenticular is, is Latin for “lens-shaped.” Most common near large mountain ranges, they form in stable environments with strong winds aloft, where moist but stable air flows over a mountain, creating standing gravity waves on the downwind (or lee) side.

Generally, the mountain range must be oriented perpendicular to the prevailing winds for these clouds to form. If the air temperature cools enough to condense the water vapor in it, a lenticular cloud may appear.

Flying saucer clouds baffle onlookers in Cape Town

Lenticular clouds can actually be used as a forecasting tool for meteorologists as they typically indicate strong winds aloft. Pilots actually use lenticulars as a sign of where NOT to fly. Since lenticular clouds are formed by strong winds and eddies or gravity waves near mountains, they indicate a turbulent atmosphere.

In other words, if you see lenticular clouds while waiting at your gate at the airport, expect a bumpy flight!

Bryan best captured the photo above of a stacked lenticular cloud over Mount Rainier, which is no stranger to lenticular clouds. Standing tall at around 14,410 feet, Mount Rainier towers above the landscape and is oriented perfectly perpendicular to the prevailing westerly winds that sweep in off the Pacific Ocean. The result? Lenticular clouds for days!

Mount Rainier, drop the mic!

Weather is awesome. #cwgpicoftheweek

(Correction: An earlier version of this posted stated an incorrect altitude for Mt. Rainier)