It's hard to believe that could happen this time of the year. When this is all figured out, I think we will find several reasons why it was so severe. Cattle hadn' developed their winter hair coat, then 2 days of rain before. Wet hair doesn't insulate very well. Cattle in summer pasture do not familiarize themselves well with areas where there is protection from the wind so more of them were caught out in the open to drift with the wind. Then there is feed. Dryer feed remains in their digestive system longer then more green or lush feed. The digestion process helps to generate heat. October is usually a dry month in western South Dakota. Winter storms do not usually arrive there until about election day.