Typically, I would tend to believe the EC map as that's what usually happens. Not sure how all of this deep snow pack will impact the temps. Downsloping compression is always an issue with SW winds.
I don't have a official method, but going to head out and do some spot measurements away from the house.
The plow came twice last night, usually for 3" or more and there's about 1"out there, so we could've gotten 6+ overnight.