The first dose of winter weather is wreaking havoc throughout northwest Iowa. The mix of freezing rain and snow has led to slick roads and dozens of cars in the ditch. Two semis blocked the roadway on Highway 60 north of Sheldon early this morning. The poor travel conditions also forced schools to close in Spirit Lake, Harris Lake Park, Sibley-Ocheydan, and South O’Brien. Other events are cancelled, from sporting events to Meals on Wheels for seniors. There’s already three inches of snow in Lyon County in the northwest corner of the state. Forecasters are calling for five inches of the white stuff by Tuesday afternoon.