Ripple Effect

Three groupings of Cirrocumulus undulatus clouds appear to be stacked on top of each other in the northeast sky around 5:20 PM on October 19, 2010. This capture was made from Bowman Woods Park in Cedar Rapids, Iowa. The characteristic ripples of undulatus are formed by atmospheric waves generated by wind shear. The clouds, existing above 16,500 feet, occur when a large area of moist air reaches saturation and forms ice crystals with instability. Also a result of ice crystals in the opposite direction of the sky at this same moment was a sun halo.