National Weather Service should be able to tell you. They have a web site, and the guys here will be able to tell you. Or... call one of the local TV stations and ask the local weather dude (or dudette), they will know right off.
Keep in mind that the site Alan refers to gives the average at the local airports for those cities listed. It IS a good starting point, however.... Things change as you move around, and Pittsburgh has a lot of hills and valleys - so there may be some considerable differences depending upon exactly where your market is located in the greater Pittburgh area. Example: if you're in the North Hills area, the snowfall total will be different than at the Pitt Airport. In Erie, the airport is located right next to the lake and the average snowfall there is 85".... but, if you go just three miles inland the "average" triples because of the lake effect and the 900 foot rise in elevation topography. Same thing happens in Connecticut and Mass, depending upon where the snowfall originates.
Your local TV weatherman (even though he cannot predict the weather to save his life), should know the nuances of the greater Pittsburgh area and the differences in the different areas of the area.