The Flash season 3 will premiere Tuesday October 4th at 8pm on The CW, Arrow season 5 will premiere in the same timeslot on Wednesday October 5th, Legends of Tomorrow season 2 on Thursday October 13th, and Supergirl season 2 on Monday October 17th.
This past spring, the finales were staggered as well – Legends of Tomorrow wrapped up its freshman season a week prior to The Flash and Arrow.
The Flash leads the pack, debuting its third season on Tuesday October 4th at 8pm, with Arrow season 5 premiering the following night, Wednesday October 5th at 8pm.
Though season 1 of Supergirl aired on CBS, the superhero drama has since been renewed for a second season that will air on The CW.