Mission and History

Our mission at High Sierra Snowcat is to provide a welcome alternative to the traditional ski resort, by providing an accessible option for backcountry skiers to ride remote terrain, sleep in cozy overnight accommodations, with safe and exceptional service. We want you to have the best day ever!

Founded in 2012 by Mike Deacon and Tim Robinson, High Sierra Snowcat was providing a human-powered overnight backcountry experience with the convenience of arriving via snowcat. Drew Layman purchased HSS after more than a decade of experience as a ski patroller and ski guide all over the world. Under this new ownership, HSS will continue to provide high-quality guided adventures with a new focus on cat-skiing throughout the terrain.

Located on the East Side of the Sierra Nevada, High Sierra Snowcat combines the use of snowcats, ski touring, and yurts to provide a safe backcountry experience in some of the wildest terrain left in California. We operate within the Humboldt-Toiyabe National Forest with nearly 9,000 acres of skiable terrain across multiple basins surrounding Virginia Lake.

We operate under an Outfitting and Guiding permit issued by the Humboldt-Toiyabe National Forest. 

Our Guides

drew layman

Drew Layman – Owner and Lead Guide

Drew is an AMGA Certified Ski Guide, giving him access to guide a wide variety of worldwide locations but he chooses to call the Eastern Sierra home. Before settling in the Eastern Sierra, Drew guided human-powered, cat, and heli-skiing in Alaska, Nepal, Pakistan, Colorado, and Utah. 

Drew has led multiple successful commercial and personal expeditions to the Himalayas and Karakoram Ranges, Icefield Range in the Yukon, the Kluchevskoy Group in Northeastern Kamchatka, and ski traverses in California. Although he is always scheming the next far-off land to go ski in, he continues to return to the Eastern Sierra year after year. He can’t get enough of the massive descents and generally sunny weather that the Sierra offer and he can’t wait to share it with you! 

Drew is also an avid climber with multiple significant mountaineering ascents in the Sierras, Cascades, and Alps in his repertoire. He spent much of his youth rock climbing with his family before moving into the back of a Honda Pilot to achieve several big wall ascents of El Capitan in Yosemite. Since then he has spent time developing crags in multiple areas around the U.S.

Finally, Drew considers himself a well-rounded outdoorsman with time spent as a competitive mountain bike racer, Class V raft guide, wilderness firefighter, SAR team member, and most recently as a paragliding pilot. 

Drew can’t wait to share his passion for skiing and vision for High Sierra Snowcat with you and looks forward to the opportunity to experience the High Sierra with you!


  • AMGA Certified Ski Guide
  • American Avalanche Association Pro II Certification
  • Wilderness EMT
  • Wilderness First Responder
  • PSIA Level 1 Ski Instructor
  • Resort Level Avalanche Forecaster and Route Leader

Tessa Andrzejczak – Operations Manager

Tessa Andrzejczak is High Sierra Snowcat’s Operations Manager and part of the Guide Team. With a degree in Tourism Management and a minor in Business Administration from Colorado State University, Tessa has held management positions at Aspen Snowmass, Big Sky, and Majestic Heli Ski. Tessa handles a lot of the back-end logistics that go into running this operation.

Born and raised in Colorado, Tessa has been following the water with the seasons throughout her life. She discovered a passion for skiing during college. Since then she has gone on to tackle peaks in the High Sierra, New Zealand, and remote corners of Alaska. Tessa’s other love is whitewater rafting, during the summer she can be found as the River Manager for Pangaea River Rafting on the Clark Fork River in Montana.

She has a passion for sharing her love of the mountains with others. Whether you interact with her via email, in the front seat of a snowcat, or skiing down a deep powder run her love of the mountains is truly infectious.


  • New Zealand Certificate in Avalanche Risk Management Level 5
  • Wilderness First Responder
  • Bachelor of Science in Natural Resource Tourism
  • Minor in Business Administration
  • Swiftwater Rescue Level 4 Certified
  • Montana and Colorado Certified Raft Guide
about us

Jamie Callanan – Lead Road Builder and Cat Driver

Jamie has lived in Mammoth Lakes for 20 years now. He loves spending time with his wife and two children, Laurel and Lundy. Jamie enjoys skiing, hiking, playing hockey and disc golf.

Jamie operated snowcats for Mammoth Mountain for 17 years. “Even after all that time, it still impresses me what snowcats are able to do. I am looking forward to being able to build new roads that will get skiers higher up the mountains, which will mean more runs and more fun for everyone.”

about us

Sarah Vossler – Guide

Sarah grew up ski racing on the East Coast before moving out West to chase big lines and deep powder. As a Mammoth Lakes resident of nine years and a backcountry enthusiast, Sarah has an in-depth knowledge of local skiing and snowpack. Often chasing the snow, she has spent multiple seasons in the southern hemisphere in Argentina, Chile and New Zealand. As both a ski instructor and ski patroller, she has worked hard developing her well-rounded skill set and her smooth, stylish skiing. Sarah is excited for another great season of high quality pow turns with the team at HSS.


  • American Avalanche Institute Pro 1
  • Professional Ski Instructors of America Level 3
  • EMT
about us

Mike Mourar – Guide

Mike grew up in Pennsylvania where he learned to ski on the icy slopes of the Northeast. He has spends most winters in the Lake Tahoe area and his summers are spent chasing rivers around the Pacific Northwest. Mike learned to guide while studying Outdoor Adventure Education at Feather River College and Southern Oregon University.  “Skiing is my greatest passion, I am fortunate to get to call the beautiful Sierra Nevada Mountains home.”


  • American Avalanche Institute Pro 2
  • AMGA Ski Guide Course
  • AIARE Course Leader
  • Wilderness First Responder
  • Bachelor of Science in Outdoor Adventure Leadership
  • Associate Degree in Outdoor Recreation Leadership