Between 1983-1988. there were 195 aviation accidents due to icing. Therefore. the FAA Icing Forecast Improvement Program was initiated in hopes to decrease the amount of aviation accidents due to icing. As part of this program. snowfall observations were collected in Eastern Colorado during 1990.... Show moreBetween 1983-1988. there were 195 aviation accidents due to icing. Therefore. the FAA Icing Forecast Improvement Program was initiated in hopes to decrease the amount of aviation accidents due to icing. As part of this program. snowfall observations were collected in Eastern Colorado during 1990. By analyzing snow depths and rates. and crystal types. the height. temperature. and the inferred of supercooled liquid water in the clouds can be determined. This will help us to better understand cloud processes involved in icing storms. This paper deals with two case studies: 27-28 February 1990. during which there was little precipitation at the ground but moderate to severe icing conditions aloft. and the 5-7 March 1990. which was a blizzard with intermittent icing conditions. Show less