Dai1y Variation Forecast of Snow-Cover Depth

The authors have already reported on the expression of daily snow-melt. In this paper，it is discussed how to apply the expression to the forecasting of dai1yo r daytime variation of snowcover depth，in order to give a special contribution to traffic business. The following results are obtained: i) Daily or daytime forecast of variation of snow-cover depth is formulated in terms of daily lowest atmospheric temperature，daily snow-fall，and certain constants. The fromula is shown in the forecast diagrams. ii) The reliability of the forecast diagrams was confirmed with 90 examples taken from the latest and past observations on the snow-cover. Error of the diagram for given quantity of snow-fall is found as 0-5cm for 73% of examples，5～10 cm for 20% and above 10 cm for 7%，when the snow-cover depth is measured in terms of new snow cover (density 0.1 g/㎤