Development of snow load design data for the United States

For development of snow load data for Standard A-58 of the U.S.A. Standards Institute it was decided that the best basis for snow load should be the observations of actual weight of snow (water equivalent) in preference to depth of snow multiplied by the density. Since structures must withstand the extreme load in any year, the annual extreme value distribution water equivalent on the ground is being employed. High elevation loads are a particular problem and work looking toward solution of this problem is discussed. Results on conversion from ground to roof and the effect of roof configuration are reviewed.