Voyager images plumes of sublimated nitrogen that reached heights of 8 km, and that were blown laterally for several hundred km.
Triton has an extremely tenuous atmosphere that has winds.
Triton underwent extreme tidal heating during the process of being captured by Neptune. Its orbit was intially very eccentric and gradually circularized. During the early stages, as it came close to Neptune it was stretched. When it was far away, it relaxed. Triton orbits retrograde and will eventually collide with Neptune or else be tidally torn apart as its orbit eventually degrades.