All of the 12z NAM numbers are in. Remember that so far the NAM has been the most aggressive of all the models with the Christmas Eve storm.
Here is a look at one of the snowfall products available on the internet.
Here is the same product but for central Indiana. (This is for my family and friends back in Indiana.)
So yes, the NAM is showing a lot less precipitation with the storm. This is the going trend amongst all the models. This doesn't mean that it is a sure bet we aren't going to get much, but it isn't looking good if you are wanting lots of snow for Christmas.
It also appears from 3D slices of the atmosphere in the model that there will probably be snow appearing on the radar early Friday but if any does begin to reach the ground it will probably be after 6pm Friday. This is because a wedge of dry air is going to be in place from 5,000 feet to 15,000 feet for much of the day. Above that wedge, there will be moisture but it will be evaporating as it moves in to the drier air. The wedge will thin through the day, but it could take a little while.
I also want to point out the lack of winter storm watches, warnings, and advisories to the west.
There are some advisories in effect across the Dakotas and Iowa, but that is it and they are just advisories. Yet another indication that forecasters are thinking this won't be a big storm.