Someone mentioned something about Virginia being the threshold for cold and tolerance for it and such.
Grandma and grandpa used to do tours to the White House every December. I joined them one year when I was about 9. I remember leaving Raleigh at about 7am or whatever it was and it was, muggy to say the least, like t-shirt and shorts weather. Well when we got to about Richmond, the snow started falling. It wasn't blizzard conditions but it was a good snowfall all the way to DC. Back in North Carolina, the weather was so unstable that tornadoes formed. Nothing serious but the system produced heavy rainstorms at the same time was dumping snow in VA. Funny thing maybe a week later snow came to Raleigh.
Edit: well maybe North of Virginia as
@Boom Boom Apathy put it, but close enough I suppose.