The mission of the Eastern Sierra Avalanche Center is to inform and educate the public on avalanche conditions in the Eastern Sierra Nevada mountains of California.

The Friends of Eastern Sierra Avalanche Center is a 501(c)3 non-profit organization overseen by a volunteer Board of Directors, outlined below. For general information, please email

ESAC employs avalanche forecasters to provide daily avalanche advisories and field observations. An administrative manager supports the forecasters and the board of directors in fulfilling our mission and expanding opportunities for local community members.




Steve Mace, Director & Lead Forecaster

Steve grew up skiing in Golden, Colorado. He began to venture outside the gates in his mid teens and never looked back. While attending college in Durango, Colorado, he continued to push his skills and knowledge earning his turns in the San Juan mountains. He has skied across the globe from Japan to the Himalaya where he helped start a ski school in Gulmarg, Kashmir. More recently Steve has worked as a ski guide in the Wallowa Mountains of eastern Oregon as well as a member of the Snow Safety department at Mt Hood Meadows. When Steve isn’t skiing he spends his time guiding raft trips on the Colorado River through the Grand Canyon.


Clancy Nelson, Avalanche Forecaster

Clancy grew up in Mammoth with skis on his feet. His experience with snow safety started in 2007 as a professional ski patroller for Mammoth Mountain Ski Area. He spent 9 years as an observer for ESAC before starting his forecasting career in 2016. Clancy spent 4 years in Montana worrying about deep slabs and surface hoar for the Flathead Avalanche Center before happily returning home to the East Side and ESAC. His academic background is in environmental science. He has a Level 3 avalanche certification from AIARE, and he’s a professional member of the American Avalanche Association. He is an AIARE course instructor, and has training from the AMGA in the ski, alpine, and rock disciplines. Clancy prefers to get around on skis, but if it’s too warm and dry you can find him chasing his partner and dog around the mountains in running or climbing shoes.


Everett Phillips, Avalanche Forecaster

Everett has worked in the avalanche safety field for over a decade. He was lucky to get his start as a ski patroller at Crystal Mountain in Washington where he discovered backcountry skiing and avalanche science. He has continued to develop those interests professionally as a ski patroller, park ranger, backcountry ski guide, and avalanche educator in California, Washington, and Colorado. Prior to working at ESAC, Everett led AIARE courses and guided backcountry skiing at Colorado Mountain School. Multi-day ski traverses are his favorite way to spend time in the mountains, especially if there are huts along the way. On his days off Everett enjoys skiing with his wife Alexa.




Rachel Drattler, Administrative Manager

Rachel grew up in the Northeast and moved to California after college to pursue her passion for climbing. With a degree in Human Ecology, Rachel has dabbled in numerous industries, traveled extensively throughout the U.S. and abroad in pursuit of remote climbing and skiing adventures. After years of working as an outdoor educator, Rachel has settled into the Eastern Sierra where she now calls June Lake, “home”. When not bounding about the Eastside, her seasonal migration leads her back to Boulder, Utah where she works as an instructor for Boulder Outdoor Survival School.




Board of Directors

Nate Greenberg – President

Forrest Cross – Vice President

Ann Piersall Logan – Secretary

Neil Satterfield – Treasurer

Allan Pietrasanta

Michelle Mather

Gabe Taylor


Walter Rosenthal – President in memoriam

Walter Rosenthal was the Snow and Avalanche Analyst for Mammoth Mountain, a remote sensing expert for the U.S. Army Cold Regions Research and Engineering Laboratory and a researcher at the Institute of Computational Earth System Science, University of California, Santa Barbara. He specialized in remote sensing of snow and snowpack processes related to sintering and avalanches. As a private consultant he provided operational subresolution snow mapping algorithms and programs to the U.S. Army Cold Regions Research and Engineering Laboratory from 1995 through 2002. Both the Army and the National Weather Service’s National Operational Hydrologic Remote Sensing Center employ his algorithms and are expanding their use to daily operational snow cover maps over North America.

Walter tragically lost his life while trying to save the lives of others in 2006. He was a vital force in the development of ESAC and is dearly missed.