More than 125 gritters worked overnight in Northern Ireland
The weather and technical problems have led to major disruption for people taking flights into Northern Ireland or travelling by train.
Radio problems caused delays on all Northern Ireland train services, whilst the snow has meant flights from England may be late.
Translink said rail journeys should be back to normal later on Tuesday.
Heavy snow had been forecast for Northern Ireland and overnight gritting took place at a cost of £200,000.
Northern Ireland escaped the worst of the snow but it affected high ground.
Translink said it had experienced radio communication problems which have since been fixed, but rail services are affected across the network.
"We remind passengers that they can use rail tickets on bus services. We apologise for the inconvenience caused," a spokesman said.
It said the problem - a failure in the train drivers' radios - was very unusual and that rail passengers travelling during rush hour on Tuesday should have a much better journey.
Earlier, departures from George Best Belfast City Airport to Leeds Bradford and Southampton were delayed.
Dublin Airport reopened its runway after it was closed for a time on Monday so that snow could be cleared.
London City airport remains closed, while Heathrow, Stansted and Gatwick airports predicted a second day of "significant delays and cancellations".
Flights at Southampton, Glasgow, Edinburgh and Aberdeen were also at risk of disruption.