This image of the storm system that generated the F-4 tornado in Moore, Oklahoma was taken by NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) instrument aboard one of the Earth Observing System (EOS) satellites. The image was captured on May 20, 2013, at 19:40 UTC (2:40 p.m. CDT) as the tornado began its deadly swath.

http://www.nasa.gov/multimedia/imagegallery/image_feature_2513.html