The move is the midfielder's second loan spell of his short Canaries career, having spent a seven-game spell at Plymouth's Home Park before Christmas.
Jarrett, who moved from Wigan Athletic on a free transfer following Norwich's relegation from the Premiership, has failed to cement a place in Nigel Worthington's first choice side after struggling with injuries at the start of the season. His move to Deepdale is expected to be completed on Monday and is done with a view to a permanent deal being completed at the end of the season.