A system includes a weight determination device and a trip control system. The weight determination device is configured to receive weather data of weather at least one of encountered or to be encountered by one or more vehicles in a vehicle system traveling on a trip along a route, and to determine a first estimated weight of the vehicle system based at least in part on the weather data. The first estimated weight accounts for mass attributable to the weather. The trip control system is configured to control the vehicle system for movement along the route based at least in part on the first estimated weight and/or display information of the first estimated weight on a display device for an operator to control the vehicle system for movement along the route based at least in part on the information of the first estimated weight that is displayed.