Since Sullivan County really is in the foothills of the Catskills, That is pretty much what you are going to get skiing wise here. Foothills. However we are within not too far driving distance to Belleayre, Hunter and Windham–all pretty major skiing resorts. And as of this week, they are all up a running. Belleayre has over 20 trails open, Windham as all of them open, and so does our closest large skiing mountain, Hunter. the snow tubing chutes are also open, and of course the accommodations as well.
Closer here to our area, we have Elk Mountain, which is just over the border in PA. It is a smaller skill hill in comparison with the larger upstate ones, however they boast a thousand feet vertical, and have over a half dozen trails. It is a little under an hour to Elk. This is the mountain I would most recommend if you own, or are planning to own in Sullivan County. It is big enough to enjoy, and you get some really nice views from the trails. The Mountainside Cafe is a nice spot to rest and get a cup of hot chocolate. There is no hotel on the mountain, but there are quite a few places to stay nearby.
Masthope is also in PA, but a bit closer. It is only a fifteen minute ride from Barryville. This is a pretty small ski resort, really good for the young ones, or a place to spend a non-challenging day. They too have a nice clubhouse, and their tubing and skiing rates are quite reasonable.
Here in Sullivan County we have Holiday Mountain a 450 foot drop with seven beginner trails. They also have a tubing hill, and ice skating for the kids. They too have a snack/lunch chalet with your agreeable winter skiing grub. Its close, and it’s a nice way to spend a winters day.