Arc'teryx Atom LT Jacket

The jacket is insulated with Coreloft™ synthetic insulation. Unlike natural down, this synthetic fill retains its warming capabilities even when wet, making it highly reliable for damp conditions.

While it uses weather-resistant GORE-TEX fabric, the Atom LT is highly water-resistant and windproof but not entirely waterproof. It is designed as an active mid-layer, meaning it sheds light rain but will eventually soak through in a heavy storm.

Yes, it is specifically designed to be layered under a hardshell ski jacket. Its trim fit and breathable side panels make it an incredibly popular choice for high-output winter sports like skiing, climbing, and snowshoeing.

The Atom LT provides reliable warmth for a lightweight insulated shell, but it is not intended for extreme, sub-zero temperatures. It excels as a standalone piece in crisp autumn weather or layered under a shell during freezing alpine ascents.