Mee has spent short periods away from the club gaining experience of senior football before, with Trafford FC and Witton Albion.
The Northern Ireland Under-21 international will regularly train with United under the terms of the agreement and can also represent Academy age-group sides in Premier League 2 and the EFL Trophy.
The young goalkeeper will further his development by playing regular competitive fixtures while being closely monitored and supported by United staff.
Everybody at United would like to wish Dermot the best of luck this term and we will follow his progress at the J Davidson Stadium closely.