Large areas of Himalayas covered with seasonal snow during winter are rapidly changing during summer, significantly affects the stream flow of many rivers originating from Himalayas. This necessitates the efficient time series monitoring of seasonal snow cover in the rugged mountainous region throughout the winter and summer periods for weekly/monthly as well seasonal forecast of stream run-off for water management and other developmental activities. In the present paper, the stream flow simulation model is implemented for a quantitative estimation of snowmelt run-off in winter and summer seasons for Beas and Parbati catchments of Beas river in Himachal Pradesh.