Whoa! Was Ghostbusters 3 filming tonight? Because those were some crazy clouds just after sunset. They appear to be a mammatus formation-- that's Latin for "bumpy clouds."
If you want to share your photos of mammatus clouds with us, tag them "gothamist" on Flickr or email them to tips(at)gothamist(dot)com. Update: Thanks for all your contributions—here's Saturday's Mammatus Clouds FOREVER gallery.