[endersshadow]

So snow is super hard to forecast because snow bands. These happen at a mesoscale, and typically one 1-2 grid points of the models used to forecast. The exact processes that contribute to banding are not very well measured, either, so it's very difficult to get a good prediction for it.

Due to the banding, you can get extreme variations in snowfall, leading to, "I thought we were supposed to get a foot, but we only got an inch!" type of comments. Or, bands will line up with the storm motion and just pelt an area harder than expected.

Example: http://imgur.com/i0j4I7g

[knz]

The Updraft blog by Minnesota Public Radio just had a small piece about how the various weather models change and what that means for local snowfall.

http://blogs.mprnews.org/updraft/2017/02/snowcover-view-from... - under "GFS model shifted". They do similar articles semi regularly.