There are areas in most northern states that are worse than others as storm tracks have lessened or worsened the results sometimes within a 100 mile radius. Let's explain what winter severity index criteria is. It is a point system that accumulates from Dec. 1 to April 1 every winter. For most states, you give the index one point for every day there is 18 inches of snow on the ground and one point for every day the temperature is below 0 Fahrenheit--maximum of 2 points each day. Some states like Minnesota start their index at 15 inches of snow. The standard is 0-50 points is mild, 51-79 moderate, 80-99 severe and 100 or more is very severe.