Jeffery La Valle, of Glenview, was pronounced dead at St. Francis Hospital in Evanston at 8:08 p.m. Sunday, according to medical examiners.
La Valle and a family member were reportedly "engaged in some horse play" after the parade when he fell off the platform and onto the third rail, according to Ald. Joe Moore (49th), who had been in contact with the Rogers Park Police District about the incident.
"He was electrocuted and died instantly," Moore said.
Police said someone had jumped onto the tracks, which carry 600 volts of electricity, in an attempt to help La Valle.
District Cmdr. Thomas Waldera declined to comment on specifics of the incident out of sensitivity to the victim's family, but confirmed that the incident had been classified as an "accidental injury."
A funeral for La Valle is planned for 7 p.m. Friday at Donnellan Family Funeral Services, 10045 Skokie Blvd., Skokie, IL, according to the funeral home's website.
"It hurts my heart that you were taken from the world too early," wrote one friend. Another wrote, simply, "Jeff, you will be missed."