There is a possiblility of snow on Wednesday 20th November.
Looking at the charts we can see a slight chance for snow at 180h out (12z on Wednesday 20th November 2013).
With the risk being at 180 hours out this is still much time for change and little confidence.
Here is the GFS Chart showing snow forecast. The snow is shown in the hatched area.
Here is the Precipitation type that shows it could be rain or snow or a mix.
Here is the snow risk.