At right is a towering CB that has reached its limit as the top of it is blown out as its neighbour is also in the same stage. Clouds of this size extend to more then 30,000 feet and will continue to drop heavy rain for several hours. The temperature differential around this cloud is moderate so that the outside down drafts are less potent then would be experience with higher temperatures. The extremely large number of toranadoes in Kansas and Southern United States is directly related to the much higher temperatures available on the surface and at intermediatel levels.
On the left is the same cloud as the one above as it passes by us to the North the formation of a stratus layer accompanies the precipitation and appears almost as a brown layer in this picture but is forming very much below the base of the of the thunderhead. Though clouds of this nature are dynamic and powerful instruments of nature this