The Club released her from the remainder of her contract, which was due to expire shortly, in order that she could link up with the NWSL power ahead of the Challenge Cup.
Jordan joined Blues last summer, from Italian side Atalanta.
Her debut season in the Barclays FA WSL yielded 18 appearances in all competitions and one goal.
The full back was an ever present in the league playing 90 minutes in all of Blues' 13 games, before the season was ended due to the COVID-19 crisis.
The Colorado Springs native, a USA Under-23s international, arrived at the Reign's pre-season training camp in Missoula, Montana, yesterday.
The Club would like to thank Adrienne for her efforts and we wish her the best of luck back in her homeland.