These are some associations and groups organized for or helpful to Nordic skiers in the downstate area. Disclaimer: aside from occasional trips with AMC chapters and the WCC, I have no participatory experience with the groups below.

Organizations promoting the outdoors and cross country skiing

American Cross Country Skiers AXCS promotes cross country skiing and acts as a resource for ‘students of the sport’

Appalachian Mountain Club (national); AMC New York-North Jersey chapter (regional) hold organized trips and meetings for people who enjoy the outdoors, including skiers.

New York-New Jersey Trail Conference promotes hiking in the metro NYC region and occasionally posts info related to cross country skiing

Organized groups for cross-country skiers

AMCski NY-NJ is a Google Group offshoot of the regional AMC chapter. One of the members has a Ski the Northeast site. Outings mainly of interest for people who want to ski backcountry or off-piste.

Miramar ski club has a website and a Meetup page
Based in Manhattan, buses leave for the club’s Vermont ski house and other destinations.

SNSA (Shawangunk Nordic Ski Association) is a club based around Minnewaska State Park. There’s a website that isn’t updated much, but the club maintains a more active Facebook page. They run races and on-snow days for newbies.

Long Island Cross Country Ski Club (https://liccsc.org/) meets in Plainview and arranges multiple trips and events.

New Hope Nordics (http://www.newhopenordics.com) is a ski club in the Philadelphia area. Their URL currently points to this page: http://prnt4u.com/nhn1.htm

Informal groups of XC skiers

Westchester Cycle Club XC ski forum is for some WCC members who are crossover Nordic skiers in winter. Join the club to get access to all their resources including the XC ski forum.

Email Groups because sometimes plain old email is good ’nuff:
NyXCski (Lower NY XC Ski)- As of Dec. 15 2020, Yahoo Groups will be discontinued. Subscribers are advised to move to mhxcss.
mhxcss (Mid-Hudson Cross Country Skiers)- just moved from a Yahoo to Google Group

XC skier-adjacent groups

AMC (Appalachian Mountain Club) is one of the oldest outdoors and conservation groups in the country. Various regional chapters run trips throughout the year, including ski trips in winter.

Meetups oriented around some other F2F appeal in addition to outdoors activities:
New York Nordic Skiing Meetup if roller-skiing in Central Park and NYC is your thing
New York backpackers is a multisport group
Sundance Outdoor Adventure Society (LGBT)
Outdoor Afro NYC
Outdoor Afro Westchester

NBS (National Brotherhood of Skiers) A large organization promoting diversity in the skiing sports and skiers who happen to be black.

Frost Valley YMCA offers Camp-style accommodations for rent, and family-oriented weekends year round.