The Chicago Transit Authority is moving to help riders on Red Line trains avoid the crush of travelers on days when the Chicago Cubs have night games at Wrigley Field. The Cubs’ home ballpark is immediately adjacent to the CTA’s Red Line Addison Street station on the city’s north side.

Calling the project a limited test program, the CTA said customers who take the Red Line north from downtown Chicago can sign up to receive text alerts about Cubs night games when the potential for heavier-than-usual…