Minnesota has a humid continental climate with distinct four seasons, and snowfall is significant in winter. Major surface flows in Minnesota include the Mississippi River, the Red River, and the Minnesota River. The Mississippi River is the largest and most significant river in Minnesota, and it is fed by several tributaries, including the Minnesota River. The region has several reservoirs/dams, including Gull Lake, Lake Mille Lacs, and Lake Superior. Minnesota's hydrology is characterized by higher-than-average precipitation levels, with rainfall and snowmelt being the primary drivers of streamflow. The state's watershed areas are the Lake Superior Basin, the Rainy River Basin, the Upper Mississippi River Basin, and the Red River Basin. Snowpack in Minnesota is essential in predicting spring and summer streamflow conditions.