one big difference between December and January weeklies is the precip anomolies. In December, they were brown or even dark red. In January they are normal or green.
ive seen many times where is a snow threat 10 days out...then its gone for a few days and then one random 00z run---it comes back. Not everytime but i would give it 24-48 hours before tossing the idea
its not normal to have these drastic changes 6-7 days out. This also happened last week when we trended from 70 degrees to 33 and Rain for Dec 26th in just a few days