Snow cover represents the amounts of water accumulated in the mountainous area. therefore, spatial and temporal monitoring of areas with snowfall potential is of great importance for predicting snowmelt, runoff and forecasting. North Khorasan province is one of the most important snowy area of the country which plays a crucial role in the feeding surface currents. So, in this study, in order to determine the areas with maximum snowfall potential, optical satellite images were used to identify the snow line and snow cover in region

. For this purpose, we used the daily production of MODIS snowcover as MOD10A2 to determine the snowcover values during 2006-2015. The above information was obtained in HDF format via FTP from MODIS Satellite Data Retention and Distribution Center, Reverb. In the following, initial processes were performed and daily surface temperature extracted. To specify the zero-degree (3-degree) isometric line, areas with the surface temperature of zero or less than zero (with 3 or less than 3) Celsius degrees were identified. Results show that, Central and Eastern half of region are the major snow-prone areas for the all three winter months (December, January and February), With the highest average of snowfall potential in January with an average of 926 pixels (230,000km2), 728 (180,185km2) in December and 569 (141,000) in February, respectively. Also the zero-degree trend line reveals the decreasing trend for January and December, while for February doesn’t show much changes. also for three-degree isotherm, the trendline shows increasing values in snow pixels.