The Saints have a had a torrid time since their promotion, with constant issues about manager Nigel Adkins' future in doubt. He has finally, however, left the club.
Adkins, 47, took the club from League One to the Premier League with successive promotions. Dowley, 25, will take charge for Southampton's first friendly game in a few days time.
The Londoner left his job of managing a local club in Barnes, South London, and will lead training for the first time today. Southampton chairman Nicola Cortese said in a statement: "This decision has been made with the long-term ambitions of Southampton Football Club in mind. Whilst we acknowledge the contribution Nigel has made during the past two years, for the club to progress and achieve our long-term targets a change was needed.
"Joe, while unknown, is a well-respected coach with youngster Luke Shaw of substantial quality who has gained a reputation with us as an astute tactician and excellent man manager. I have every confidence that he will inspire our talented squad of players to perform at the highest possible level."
Adkins' Southampton Record
- Played: 124
- Won: 67
- Drawn: 25
- Lost: 32