There is disruption on the roads in the Anglia region and airports are warning of delays as heavy snow is falling across much of the area.
London Luton Airport said passengers should allow extra time for their journey to the airport and contact their airline for further information.
Highways England says it is working closely with the Met Office monitoring the latest weather conditions with snow expected to affect the road network during Sunday.
The Beds, Cambs & Herts Roads Policing Unit says the A421 is closed eastbound at the Black Cat roundabout because of a jack-knifed lorry.
Persistent heavy snowfall is expected in the region throughout the morning, leading the Met Office to issue an amber weather warning that will be in place until 6pm.
Up to 10cm (4 inches) is expected to build up quite widely, with 15-20cm (6-8 inches) in some spots, raising the prospect of roads becoming impassable.
Highways England advised road users across the Midlands and northern England to check the forecast and routes before heading out as a section of the M1 was closed.
The authority tweeted that traffic had stopped on the M1 northbound between J16 and J17 due to "numerous break downs/stuck vehicles".