Coach Stumpo spent the past three years as the head coach at Northland College in Ashland, Wisconsin. In his final season, he set the program record for wins in a season and leaves Northland with the most wins by a men's lacrosse coach there. In the 2022 season, they finished the year ranked second in the country in caused turnovers per game, 15th in the country in man-down defense, and 33rd in goals against average. He doubled the number of athletes on the roster in his time there, and when he was hired at Northland, he was the youngest active NCAA head coach.

Prior to his time at Northland, he was the head coach at Hargrave Military Academy, where he was also the Student Activities Director. There, he oversaw all lacrosse-related activities, which included a significant focus on promoting the need for team members to be academically focused while striving for athletic growth. He also was in charge of planning and scheduling all on and off-campus extracurricular activities for the student body.