The 2017 Yellowstone construction schedule is posted. There are two major impacts on visitors.
This is the 3rd year (out of six) of totally reconstructing the roadway from Norris to Mammoth (actually to Swan Lake Flat). Once again there will be nightly closures of the road and then a full closure in the fall for 4 weeks. Here is the official word from the NPS web site:
"Norris to Mammoth: expect 30-minute delays between Roaring Mountain and the Indian Creek Campground beginning April 21, 2017. From June 1 to September 10, this section of road will be closed during the night (10 pm to 7 am). From September 10 to October 6, this section of road will be closed to all traffic (day and night). Norris and Indian Creek campgrounds will remain open."
The second area of construction impacting visitors this year is at Canyon, where they are doing a multi-year reconstruction of the overlooks, trails and parking areas.
"Canyon Area: the Brink of Upper Falls and Inspiration Point are closed for the season."
I still have not seen any definitive word about when the construction on the Grand Prismatic Spring overlook will be completed and the Fairy Falls trail re-opened. I presume they will announce a date once they get back to work on that project this spring and see how quickly things progress.