According to this CWG article: https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/01/12/everything-you-need-to-know-about-snow-in-washington-d-c/?utm_term=.faff75a19b3e
The average Moderate La Nina winter gives DC 10.8" of snow, which is also near the Median I believe. Certainly not awful, but bad from the typical standpoint of course.