After watching the same ridiculous news reporting touting "historic", "storm of the century", "unprecedented", etc., year after year, the more cynical side of me suggests that there's a small supplemental reason besides flawed models: there's probably good money to be made from overhyping storms. At the very least news stations must get great ratings the day or two beforehand. Note that this doesn't preclude accurate estimating...you just have to pull a bunch of cheap psychological tricks to get people to focus on the worst case scenario. The end result of people freaking out is still largely the same.

One reason this comes to mind is that I can't ever remember a storm reaching its worst-case snowfall predictions, and usually they barely make the minimums. A rule of thumb I use is to treat the minimum prediction as the actual maximum and zero as the actual minimum. Anecdotal, but seems to work well.