Shane Matthew Guess

Shane Matthew Guess passed away peacefully on September 11, 2026, at his home in San Luis Obispo after two years of bravely facing glioblastoma, a fast-growing, aggressive type of cancerous brain tumor. Born in Glendale, CA, on September 1, 1980, he was 46 years old and is survived by his mother, Janette Guess, and his sister, Kristin Guess, both of whom reside in San Luis Obispo. Shane was preceded in death by his father, Richard "Dick" Corbett Guess, Jr., who passed away on April 5, 2023, at his home in San Luis Obispo. Born in Jackson, Mississippi, in 1947, Dick was 75 years old.

After graduating from San Luis Obispo High School in 1998 as salutatorian, Shane earned his Bachelor of Science in Nuclear Engineering from the University of California, Berkeley in 2002, and later completed his Master of Business Administration from the University of La Verne in 2008. A proud Golden Bear, Shane carried his Cal spirit with him throughout his life and career.

Shane built a long and dedicated career in the nuclear power industry, devoting more than 24 years to Pacific Gas and Electric Company at Diablo Canyon Power Plant, where he rose through the ranks in remarkable fashion. Beginning as an intern directly out of college and ultimately serving as a Director, his career reflected both his deep technical knowledge and his exceptional ability to lead and inspire those around him. He was known for his sharp mind, steady work ethic, and genuine kindness toward colleagues.

Beyond his professional life, Shane loved his family and friends fiercely. He was especially proud of his Scottish heritage on his mother’s side and enjoyed researching his family clan and connections on Ancestry.com. He often spoke of how much he missed his Scottish Nana and Papa, who are in heaven.

Shane loved the Central Coast deeply, especially Morro Bay, where he spent countless mornings and afternoons walking the Embarcadero, watching the sea otters, chatting with locals, and capturing his favorite scenic views. He found peace in the ocean air and joy in the simple ritual of a good shot of espresso at Scout Coffee Co. His love of exploration extended far beyond California. Shane was a true adventurer, traveling the world with his friends to places like Africa, Croatia, Iceland, Tasmania, the Seychelles, and Colombia (to name a few!).

Wherever he went, he embraced new experiences, from fine dining and wine to local traditions, always eager to explore, learn, and savor the journey. He never missed an opportunity to brighten someone’s day with humor, curiosity, or a thoughtful conversation, and at every meal he would lift his glass to celebrate life, always finding joy in the little things. Shane also loved history, languages, aviation, music, puzzles, and his stuffed animal collection, especially Scotts, the white Scottish Terrier who wore a wee tartan bonnet and scarf!

Shane had set a goal to visit all 50 states in the United States before he passed, and technically he met this goal, though he always insisted that his brief “border hop” into Arkansas didn’t count as a real visit. He joked that he had 49 out of 50 states plus one technicality, and he was determined to go back and plant both feet firmly in Arkansas to make it official.

Having successfully managed juvenile diabetes since the age of nine, he was also a passionate supporter of autoimmune therapy research.

With his infectious laughter and generous heart, Shane brought joy to the lives of so many. He will be remembered for his gentle spirit, his loyalty to family and friends, and the way he made every person feel seen and valued. He will be missed by all who loved him.

If you would like to honor Shane’s legacy as a nuclear engineer who loved Cal and who recently became an advocate for glioblastoma research, we ask that donations be made in Shane’s memory to:

UCSF Neurosurgery Brain Tumor Fund

Benefiting the research of Dr. Thomas Nelson, a fellow engineer turned neuro oncologist who provided Shane with excellent care.

https://giving.ucsf.edu/fund/neurosurgery-brain-tumor-fund

Under “Gift Options,” please make your gift in honor of Shane Guess. All gifts made in Shane’s honor will support Dr. Thomas Nelson’s brain tumor research at UCSF.

UC Berkeley Nuclear Engineering Excellence Fund

https://give.berkeley.edu/fund/FU1077000

In honor of Shane’s legacy and his deep connection to nuclear engineering, his family requests that memorial gifts be directed to the Berkeley Nuclear Engineering Department. These contributions will support future generations of nuclear engineers and carry forward the spirit of leadership and dedication that defined Shane’s remarkable life.

To make an online gift in memory of Shane Matthew Guess, please click the link above. When completing the form, be sure to enter “Shane Guess” in the “In Memory Of” field. Please also include Kristin Guess at [email protected] in the gift notification section so the family may be informed of your generous contribution.

Alternatively, you may contact Eileen Morris at [email protected].

Go Bears.