Motorists will be unable to get onto the M25 from the southbound M1 in the latest set of road closures.

Testing works will be going ahead between December 9 and December 14, causing the M1 junction with the M25 (junction 6a/21) to close between 10pm to 6am each night.

During those times, a diversion via National Highways and Hertfordshire County Council maintained roads will be in place.

See the full list of M25, M1, and A1M closures near Watford below:

M1:

From 10pm November 26 to 5am November 29: Slight delays (under 10 minutes). Southbound, junction 7 to junction 6a. Lane closure for electrical works.

From 10pm November 28 to 5am November 29: Slight delays (under 10 minutes). Southbound, junction 6 to junction 5. Lane closures for structure inspections.

From 10pm November 27 to 5am November 29: Slight delays (under 10 minutes). Southbound, junction 6 to junction 5. Lane closures for structure inspections.

From 10pm December 9 to 5am December 11: Slight delays (under 10 minutes). Southbound, junction 4 to junction 3. Lane closures for structure inspections.

From 10pm December 9 to 6am December 14: Moderate delays (10-30 minutes). Anti clockwise, junction 21A to junction 20. Carriageway closure for testing works. Diversion via National Highways and local authorities roads.

M25:

  • (In progress). From 8pm September 30 to 6am December 20: Moderate delays (10-30 minutes). Clockwise, junction 23 to junction 24. Lane and slip road closure for scheme works. Diversion via National Highways roads.
  • (In progress). From 10pm November 13 to 5.30am November 28: Slight delays (under 10 minutes). Clockwise, junction 21 to junction 22. Lane closures for weather installation works.
  • From 10pm November 20 to 5.30am November 30: Slight delays (under 10 minutes). Clockwise, junction 24 to junction 25. Lane closure for Midas installation works.
  • From 10pm November 25 to 5.30am November 27: Slight delays (under 10 minutes). Anti-clockwise, junction 25 to junction 23. Lane closure for emergency area upgrade works.
  • From 10pm November 26 to 5am November 29: Slight delays (under 10 minutes). Anticlockwise, junction 7 to junction 6A. Lane closure for electrical works.
  • From 10pm November 27 to 5am November 28: Moderate delays (10-30 minutes). Anticlockwise, junction 22 to junction 21A. Lane and carriageway closure for urgent safety fence repairs. Diversion via National Highways.
  • From 10pm November 28 to 5am November 29: Slight delays (under 10 minutes). Anticlockwise, junction 22 to junction 21A. Lane closure for urgent safety fence repairs.
  • From 10pm November 28 to 5am November 29: Slight delays (under 10 minutes). Clockwise, junction 21A to junction 22. Lane closure for urgent technology works.
  • From 11pm November 29 to 6am November 30: Slight delays (under 10 minutes). Clockwise, junction 23 to junction 24. Lane closure for Midas Installation works.
  • From 10pm December 4 to 5.30am December 6: Slight delays (under 10 minutes). Anti-clockwise, junction 24 to junction 23. Lane closure for emergency area upgrade works.
  • From 11pm December 6 to 5.30am December 7: Moderate delays (10-30 minutes). Anti-clockwise, junction 24 to junction 23. Lane and slip road closure for emergency area upgrade works. Diversion via National Highways roads.
  • From 10pm December 9 to 5.30am December 10: Slight delays (under 10 minutes). Clockwise, junction 23 to junction 24. Lane closure for Midas installation works.
  • From 10pm December 9 to 6am December 14: Slight delays (under 10 minutes). Clockwise, junction 21 to junction 22. Lane closures for weather station instillation works.

A1(M):

  • From 10pm November 26 to 5am November 27: Slight delays (under 10 minutes). A1(M) southbound, junction 2 to junction 1. Lane closure for urgent pothole repair.
  • From 10pm November 26 to 5am November 27: Slight delays (under 10 minutes). A1(M) northbound, junction Bignells corner to junction 23. Roundabout, lane closures for urgent safety fence repairs.
  • From 10pm December 2 to 5am December 4: Moderate delays (10-30 minutes). A1M southbound, junction 2 to junction 1. Lane and carriageway closure for electrical works. Diversion via National Highways roads.
  • From 10pm November 27 to 5am November 28: Slight delays (under 10 minutes). A1 southbound, junction Bignells corner to junction Rowley Lane. Lane closure for urgent safety fence repairs.
  • From 10pm November 28 to 5am November 29: Moderate delays (10-30 minutes). A1(M) southbound, junction 2 to junction A1 southbound, junction Bignells corner. Lane closure for carriageway repairs, diversion via National Highways.
  • From 11pm December 6 to 5am December 7: Moderate delays (10-30 minutes). M25 clockwise, junction 23, A1 northbound, junction Bignells corner and A1(M) southbound junction 2 to junction Bignells corner. Lane and slip road closure for asset inspections. diversion via local authority and National Highways roads.
  • From 10pm December 9 to 5am December 10: Moderate delays (10-30 minutes). A1(M) northbound, junction 1 to junction 3, carriageway closure, entry slip road closure and lane closures for maintenance works. Diversion via National Highways and local authority roads.

A roads:

  • A405 - From 10pm November 25 to 5am November 26, slight delays (under 10 minutes). M1 southbound, junction 9 to junction 8. Lane closure for communications on behalf of National Highways.
  • A414 - From 9pm November 26 to 5am November 27, slight delays (under 10 minutes). Eastbound, Breakspear Way Roundabout to Park Street Roundabout. Lane closure for litter clearance on behalf of National Highways.
  • A414 - From 10pm November 28 to 5am November 29, moderate delays (10-30 minutes). Both directions, Park Street Roundabout to Breakspear Way Roundabout. Carriageway closures, lane closures and diversion routes for drainage on behalf of National Highways.