Stacked Lenticular Cloud

May 04, 2011

Lenticulatover AZ 
Photographer: Stan Celestian
Summary Author: Stan Celestian; Jim Foster

The photo above showing a striking, stacked lenticular cloud (Altocumulus lenticularis) was taken near Waddell, Arizona. Lenticular clouds are a type of wave cloud that form when a layer of air near the surface is lifted and cools. This usually happens because of orographic lifting over a topographic feature -- wave clouds form on the lee side. In the middle latitudes, lenticular clouds typically are found between 6,500 and 15,000 ft (1,981 and 4,572 m) above the surface. Even though it may be windy aloft and at the surface as well, as it was on this April day, lenticular clouds can appear almost motionless with respect to the terrain since they form at waves crests in stationary air currents. Because sufficient moisture was available and the airflow was strong, this wave consisted of layers of lenticulars stacked on top of each other. Photo taken on April 18, 2011.

Photo details: Camera Maker: NIKON CORPORATION; Camera Model: NIKON D200; Focal Length: 102mm (35mm equivalent: 153mm); Aperture: f/7.1; Exposure Time: 0.0050 s (1/200); ISO equiv: 100; Exposure Bias: +0.67 EV; Metering Mode: Spot; Exposure: program (Auto); White Balance: Manual; Light Source: Fine Weather; Flash Fired: No; Orientation: Normal; Color Space: sRGB.