National Parks: closed, but you can drive by the Tetons on HWY 89
US Forest Service land is not closed by the government, except for developed areas like campgrounds.
Many of the forest trails/roads are still under mud/snow and are not really passable. This varies by location and day to day.
We had a pretty big snow year this year. We also did not get our January thaw like normal. There is still lots of snow in the mountains.
Restaurants in Jackson are open for carry out and delivery only. Some hotels are still open and the 14 day quarantine ends at midnight tonight so you can wander about freely (as long as you are 6 feet from all other humans and wear a mask where virus distancing is not possible).
All of the bars and night life are shut down, but all of the liquor stores and grocery stores are open.
All of the bike paths are open, so if you're into cycling there are lots of options for pounding pavement.
We are seeing more and more out of state plates every day. People want to get away from wherever they are and some are coming here. You will not have the full Jackson/Tetons/Yellowstone experience as normal.
Check out
JHCOVID.com for the latest details on local health orders and sitrep for infections, etc.