The 23-year-old's only appearance for the Cobblers this season was as a 75th-minute substitute in the 1-0 Johnstone's Paint Trophy win over MK Dons.
He will join Stockport for a period of 93 days and return to his parent club on December 22.
Turnbull spent six years at Edgeley Park between 2005 and 2011. He also spent the second half of last season on loan at his former club.
Restore Data
| Team | P | W | D | L | F | A | GD | PTS | |
| 1 | Birmingham CityBirmingham | 8 | 7 | 1 | 0 | 17 | 8 | 9 | 22 |
| 2 | Wrexham | 9 | 5 | 2 | 2 | 14 | 7 | 7 | 17 |
| 3 | Mansfield TownMansfield | 8 | 5 | 2 | 1 | 15 | 11 | 4 | 17 |
| 4 | Stockport CountyStockport | 8 | 4 | 3 | 1 | 13 | 7 | 6 | 15 |
| 5 | Lincoln CityLincoln | 8 | 4 | 3 | 1 | 13 | 7 | 6 | 15 |
| 6 | Blackpool | 9 | 4 | 3 | 2 | 17 | 14 | 3 | 15 |
| 7 | Barnsley | 9 | 4 | 3 | 2 | 15 | 13 | 2 | 15 |
| 8 | Wycombe WanderersWycombe | 8 | 4 | 2 | 2 | 16 | 13 | 3 | 14 |
| 9 | Stevenage | 9 | 4 | 2 | 3 | 7 | 5 | 2 | 14 |
| 10 | Exeter CityExeter | 8 | 4 | 1 | 3 | 9 | 6 | 3 | 13 |
| 11 | Bolton WanderersBolton | 8 | 4 | 1 | 3 | 13 | 13 | 0 | 13 |
| 12 | Reading | 8 | 4 | 1 | 3 | 12 | 12 | 0 | 13 |
| 13 | Charlton AthleticCharlton | 9 | 4 | 1 | 4 | 9 | 9 | 0 | 13 |
| 14 | Wigan AthleticWigan | 9 | 3 | 3 | 3 | 9 | 5 | 4 | 12 |
| 15 | Huddersfield TownHuddersfield | 9 | 4 | 0 | 5 | 12 | 11 | 1 | 12 |
| 16 | Peterborough UnitedPeterborough | 9 | 3 | 2 | 4 | 14 | 17 | -3 | 11 |
| 17 | Rotherham UnitedRotherham | 9 | 2 | 4 | 3 | 7 | 10 | -3 | 10 |
| 18 | Bristol Rovers | 9 | 3 | 1 | 5 | 10 | 15 | -5 | 10 |
| 19 | Northampton TownNorthampton | 8 | 2 | 2 | 4 | 10 | 13 | -3 | 8 |
| 20 | Leyton Orient | 9 | 2 | 2 | 5 | 9 | 12 | -3 | 8 |
| 21 | Crawley TownCrawley | 8 | 2 | 1 | 5 | 5 | 12 | -7 | 7 |
| 22 | Burton Albion | 8 | 0 | 4 | 4 | 9 | 16 | -7 | 4 |
| 23 | Shrewsbury TownShrewsbury | 9 | 1 | 1 | 7 | 6 | 15 | -9 | 4 |
| 24 | Cambridge UnitedCambridge | 8 | 0 | 1 | 7 | 6 | 16 | -10 | 1 |
| > League One Full Table | |||||||||
