I have updated the news, conditions and prospects for January along with the updating the season background for winter, with a map for the NP. All of this pretty much is what you would expect, snow everywhere but the northwest corner which is snow free to about 3,000 feet.
The snowplay area will not open until the snowpack is 5 feet at Paradise which will be sometime in early January, earlier if there is a rash of snowstorms come through the area and the NP. Warmer temperatures in late December after some snowstorms in the week or so before melted some of the snow to where it is lower than 5 feet.
The Jackson visitors center is open daily through January 2 and then resorts to the weekend and holiday schedule into May. This means after the New Years holiday there will be no services at Paradise on weekdays. In addition the cold weather and snow is requiring chains on 2WD cars most days beginning anywhere from Longmire to Cougar Rock campground.
Before you go you should check the NP's Twitter Account for the latest road conditions and snow conditions at Paradise. It will save you driving time if everything is closed or help to be ready to sit awhile at Longmire until the gate is open.