Hi Stephen,
I do the majority of my hiking in the Adirondacks and love it up there in the winter. Fewer people, fewer bugs, and trails that usually require rock hopping are leveled out with the snow. Tons of fun. My buddy and I went up there last year for two nights during one of the -20F (-29C) weekends. It was not something that either of us was seeking out, but I felt good with what I had.
Bag: Western Mountaineering Kodiak MF 0 Degree (overstuffed)
Pads: Thermarest RidgeRest Sleeping Pad and BMW Torsolite
Head: Outdoor Research Wind Pro Balaclava
Hands: Outdoor Research Meteor Mitt Liners
Feet: Smartwool Mountaineering Extra Heavy Crew Socks
Legs: Patagonia Capilene 3 Midweight Bottom
Torso1: Patagonia Capilene 3 Midweight Zip Neck
Torso2: Outdoor Research Transcendent Sweater (draped this over me inside my bag like a blanket)
Tent: SMD Lunar Duo
I was somewhat surprised at how comfortably I slept. The only times I felt cold were when a body part would migrate off my pad and hit the ground. I now have a Downmat UL7 and I know that will help keep me warm this upcoming season.
In my humble opinion, the items required for the winter mountaineering course are somewhat overkill for the area. However, I hope to attend the school someday if only to learn how to properly use said gear.
I hope this helps and I agree with James…you'll have a great time!