British Airways was forced to cancel almost 10% of its flights from London's Heathrow Airport this morning because of the bad weather.
A spokesman said 54 short-haul flights to destinations in the UK and Europe had been affected but added that the weather had since improved and no further cancellations were immediately anticipated.
Parts of London - which has been largely unscathed by snow all week - and the Thames estuary were covered by snow overnight, although the worst conditions remain in Northumberland and the Scottish Borders.
The BA spokesman said that on an average day the airline has about 550 services departing from Heathrow. Destinations affected by the bad weather included Manchester, Edinburgh, Brussels, Dusseldorf, Copenhagen, Zurich and Geneva.
The spokesman said: "We are apologising to passengers, 54 flights were cancelled from Heathrow this morning due to snow. They were all UK and European destinations so it does give us some flexibility on transferring them."
BA has set up an information hotline on 0800-727 800, which passengers can call before they travel to the airport, or they can log on to the BA website.
Earlier, the Met Office issued a warning to motorists across the UK about icy driving conditions, although extensive gritting on major routes was helping. Conditions were reported to be especially hazardous in East Anglia and south-east England after freezing temperatures overnight.
Despite the gritting, traffic experts warned that ice and further downfalls remain a danger for drivers. Motorists were warned to be particularly careful on any roads that had not been gritted.
Forecasters said the snow around the country would be melting away throughout the day as temperatures rose slightly and rain started to fall. However, further snowfall was expected in Northumberland and the Scottish Borders, and weather experts warned that sleet and drifting snow around the country could still cause problems.
Warmer weather is expected to arrive over the weekend, but while the worst may be over, forecasters predict that the cold snap will extend well into next week. Up to 1cm more snow could still fall in some areas, and temperatures were expected to drop below freezing again tonight.
Forecasters admitted yesterday they had been unduly pessimistic after much of the snow expected in southern and western parts of the country had failed to materialise.
Earlier in the week, weather experts predicted that yesterday would be the bitterest day of the cold snap, with widespread snow across southern as well as northern England. In the event, much of southern England escaped the heavier snowfalls that have affected northern and central parts of Britain, causing problems on the roads in those areas.
Paul Mott of the PA WeatherCentre said the next few days would be drier and brighter, but most parts of the country would remain cold, with temperatures reaching a maximum of 4C (39F).
Many schools across the country remained closed today with some pupils enjoying an unexpected day off in Kent, Yorkshire, Cheshire, Derbyshire, Norfolk, Surrey and Lancashire. More than 600 schools were closed across the UK yesterday.
Roads closed include the A686 in Cumbria, A689 in West Yorkshire, A66 in Durham and A640 in Huddersfield. "Conditions this morning have been a lot better than the last two days, with all motorways and most major routes open," said an RAC spokeswoman. "That is largely down to a night of gritting, gritting and more gritting, and we are still advising motorists to take care, as the ice and slush will cause problems."
Yesterday, even professional motorists were caught out by the blizzard conditions. Police and RAF helicopters mounted a joint operation to rescue an RAC patrolman who was stranded at Rosedale Abbey, high on the North Yorkshire moors.
The PA WeatherCentre said the southern half of England and Wales would see a fair amount of cloud and some patchy sleet tonight, with snow in places, but there would be a few clear spells as well. More northerly parts of England and Wales may see a few wintry showers for a time, but some clear spells will gradually develop as the night progresses.
Northern Ireland and Scotland should be dry just about everywhere, with variable amounts of cloud and some clear spells. A widespread and locally sharp frost will develop across the country.
