Here is some possibly kind of dry documents that I came across on the CollectSpace forums. There is a bit of Calculus and scary graphs, but still a bit of easy to understand English in there also. So of the Saturn V blew up on the ground there would be a fireball which would last about 33 seconds (20 seconds for the smaller Saturn 1B) and a temperature of up to 2500 degrees F.
The other document has some estimates on how fast the crew could escape from the mess if they pulled the abort handle to fire the escape rocket. Unlike the shuttle, failure did have an option.