The Nittany Lions will raise their championship banner on September 5 against Kentucky.
Dowd is tied for the most assists by a defenseman in program history.
"I think our goal is to always win, and these guys have really high expectations."
The right-handed setter becomes the fourth recruit in the class of 2027.
The outfielder joins after spending two years at Trinity University.
Izzy Starck, Kennedy Martin, and Gillian Grimes were named to the Preseason All-Big Ten Team.