Techniques are described for using geographic location data of snowplows to update a snow depth associated with a section of a surface street. The route of the snowplow may be tracked continuously which allows the snow depth of the street to be reset in real-time. The updated snow depth may then be used to generate a cost of travelling on the street. The travelling cost may then be used to plan a route through the region. Alternatively, the cost may be graphically displayed on a map to permit a user to determine which surface streets to avoid. In another embodiment, the cost of travelling on a particular street may be changed by the attributes of the vehicle that will navigate the snow-covered roads, driver's experience, or the geographic terrain of a road. This new cost may then be used, for example, to plan a route or display roads to avoid.