16 August 2011

Is it A Cloud or A Shadow

Posted by Dan Satterfield

A viewer (Eric Atkins) sent me this pic a few weeks back, and it has stumped quite a few meteorologists including me! At first it looks like the cloud in the foreground is casting a shadow on the cirrocumulus deck above and behind it, but this cannot be so! The sun is behind the cloud and not opposite the view from the camera. I have some fellow meteorologists looking into it around the country, but it may very well be a shade being cast on a haze layer above.

Meteorologist Roger Edwards at the Storm Prediction Center in Norman is an avid weather photographer and he has a very similar image here. I’m emailing him and will let you know what he thinks.

Update 16 Aug. : from Roger Edwards:

Dan,

You’re right on track.  I took a similar photo back in 1996, from a similar sun-relative angle:
http://www.stormeyes.org/tornado/SkyPix/gem8ne.htm