National Highways Regional Operations Manager Dee Murray said the agency had a “massive operation” out overnight using gritters on the roads.
He said although there was not as much snow as expected, drivers still needed to take care while driving.
Mr Murray told BBC Radio Manchester it was “still very cold out there”.
“It’s not maybe as visible, the danger, because there’s not as much snow,” he added.
He said drivers should ensure their cars are fully fuelled and topped up with windscreen wiper fluid before beginning their journeys, and should take warm clothing, a torch and an “old school map” in case of becoming stranded.
“Just think what’s going to happen if you have to get out of that nice warm car and you can’t keep the heater on,” he added.
The UK Health Security Agency has issued an amber cold health alert, external for the whole of the North West, which is in place until 18:00 GMT on Saturday.
The agency said the weather conditions would lead to an increased risk to older and vulnerable people and would likely have a significant impact on health services.
The Met Office UK said a yellow warning, external for snow and ice would remain in place until 11:00 GMT, with “another chilly night to come with but largely clear skies allowing a frost to form”, and a minimum temperature of -1C.