Tammas “Tam” F. Kelly, M.D., 69, passed away Thursday, March 19, 2026, in Sioux City, IA.

A Celebration of Life will be held at 5:00 p.m. on Saturday, May 9, at the Sioux City Country Club.

Tam was born September 28, 1956, in Sioux City, to Frederick and Ramona Rowe Kelly. He graduated from North High School in 1975, where he was active in football, basketball, and cheerleading. He went on to earn both his Bachelor of Science and Doctor of Medicine degrees from the University of Iowa graduating in 1985.

Later that year he married Cynthia Van Farowe, M.D., whom he met in medical school. They completed their residencies in Phoenix, Arizona—Tam in psychiatry and Cynthia in family practice. Drawn by their love of the outdoors, they settled in Fort Collins, Colorado, where they raised their daughters, Sarah Rose Kelly and Blair Skye Kelly.

After several years in private practice, he joined Mountain Crest Hospital for Behavioral Health, where he eventually served as President of the Medical Staff. In 1990 he founded The Depression & Bipolar Clinic of Colorado which specialized in diagnosing and treating hard-to-treat Bipolar II disorders. He was successful in this as many grateful patients can attest. During this time, he was appointed Associate Clinical Professor of Psychiatry George Washington University School of Medicine which helped him publish his research findings.

In 2021 Tam closed his private practice in Fort Collins, CO and moved to Buffalo, NY to join the University of Buffalo Department of Psychiatry to continue his practice and research.

In his nearly 40 years of practice, he became the preeminent psychiatrist in the field of treating Bipolar II, soft bipolar and Spectrum Disorder. He was the lead author of 12 peer reviewed research papers, more than any other psychiatrist and was among the first to identify the high prevalence of obstructive sleep apnea—affecting approximately 47%—in bipolar patients. He authored two books, the first “The Art and Science of Thyroid Supplementation for the Treatment of Bipolar Depression” and “A 1001 Pearls for Diagnosing and Treating Bipolar II/Subthresshold Bipolar.”

In September of 2025 he retired and moved back to Sioux City.

He is survived by his daughters, Sarah of Brooklyn, New York, and Blair of Orlando, Florida; his former wife, Cynthia of Fort Collins, Colorado; his brother, Tate (Margaret) Kelly of Arlington, Texas; nephew Kirk Kelly; niece Cara Lentz; and many, many cousins. He was preceded in death by his parents.

He had a wicked sense of humor. Without doubt, we will all miss his twinkling eyes and slight smile as he quietly delivered a devastating pun that always came without warning.

The family wishes to express our deep gratitude to Heart of Siouxland Senior Care for the care and comfort they extended Tam in his final months.

(Note – if you plan to attend the Celebration of Life, please RSVP to tkeller1979@gmail.com.)