Railroad traffic changes throughout the year, and the seasonal variations in rail traffic provide opportunities to vary the operations of our model railroads in ways that add interest and realism while reducing repetition. The growing season, the heating season, the construction season, and various holiday seasons all affect what is shipped and how much is shipped by rail, and these can all be modelled. Based on information about prototype practices, and based on operations on my HO-scale Carleton Railway, this clinic will present practical ideas about how to incorporate seasonal variations to your industries, your rolling stock, and your operating scheme.