If you work downtown, you might want to make a note to take an alternate route to the office. Much of the Western Gateway Park area will be closed for the 80/35 music festival. As of midnight tonight, Locust Street and Grand Avenue will be closed between 10th and 15th streets. Cross streets 12th, 13th and 14th will be closed between Walnut Street and Locust Street or Grand Avenue. The closures begin tonight at midnight, and streets will be open by 6 a.m. Monday.