Snow-covered hills around the Holy Trinity Anglican church in Aghnahily, Co Laois, Ireland. Picture: Niall Carson/PA via AP
Snow-covered hills around the Holy Trinity Anglican church in Aghnahily, Co Laois, Ireland. Picture: Niall Carson/PA via AP
A snowman and dog on a bench in Worcester, England. Picture: David Davies/PA via AP
A snowman and dog on a bench in Worcester, England. Picture: David Davies/PA via AP
People walk through snow on the coast at Whitley Bay, northeast England. Picture: Owen Humphreys/PA via AP
People walk through snow on the coast at Whitley Bay, northeast England. Picture: Owen Humphreys/PA via AP
Snow covers Ironbridge, England, as heavy snow falls across parts of Britain. Picture: Nick Potts/PA via AP
Snow covers Ironbridge, England, as heavy snow falls across parts of Britain. Picture: Nick Potts/PA via AP
A woman walks away from Notting Hill underground station as snow falls in London. Picture: Alastair Grant/AP
A woman walks away from Notting Hill underground station as snow falls in London. Picture: Alastair Grant/AP
A farmhouse in Durham, England, is seen as heavy snow falls across parts of Britain. Picture: Owen Humphreys/PA via AP
A farmhouse in Durham, England, is seen as heavy snow falls across parts of Britain. Picture: Owen Humphreys/PA via AP
Snow falls as a woman crosses Oxford Street in London filled with early shoppers. Picture: Alastair Grant/AP
Snow falls as a woman crosses Oxford Street in London filled with early shoppers. Picture: Alastair Grant/AP
Manchester City' players warm up as snow falls before the English Premier League soccer match between Manchester United and Manchester City at Old Trafford Stadium in Manchester, England. Picture: Dave Thompson/AP
Manchester City' players warm up as snow falls before the English Premier League soccer match between Manchester United and Manchester City at Old Trafford Stadium in Manchester, England. Picture: Dave Thompson/AP
People enjoy a snow covered hill near Princes Risborough, Buckinghamshire, England. Picture: Steve Parsons/PA via AP
People enjoy a snow covered hill near Princes Risborough, Buckinghamshire, England. Picture: Steve Parsons/PA via AP
Snowy conditions in Danbury, south-east England. Picture: Gareth Fuller/PA via AP
Snowy conditions in Danbury, south-east England. Picture: Gareth Fuller/PA via AP
People walk through snowy conditions in Danbury, south-east England. Picture: Gareth Fuller/PA via AP
People walk through snowy conditions in Danbury, south-east England. Picture: Gareth Fuller/PA via AP
A walker visits the snow-covered ruins of Dunamase castle on the Rock of Dunamase in Aghnahily, Co Laois, Ireland. Picture: Niall Carson/PA via AP
A walker visits the snow-covered ruins of Dunamase castle on the Rock of Dunamase in Aghnahily, Co Laois, Ireland. Picture: Niall Carson/PA via AP

London - Snow and wintry weather are still wreaking havoc on travelers in Britain, with flights cancelled, roads sheathed in ice and rail travel disrupted on Monday.

With temperatures predicted to drop overnight to as low as minus 12 Celsius (11 degrees Fahrenheit), transport officials worked on cleanup. Hundreds of schools were closed and airports struggled under the weight of flight delays.

"The worst of the snowfall is behind us," said Grahame Madge of the Met Office. "It's now more about dealing with the weather we've had."

Europe's largest airport, Heathrow, warned that hundreds of flights would be cancelled as it cleared the backlog of flights delayed by Sunday's snowfall.

In the world of interconnected air travel, any extended disruption quickly leaves planes and flight crews out of position, knocking them out of the rotation for their next assignments. Airlines are also responsible for de-icing their aircraft, and some have more capacity than others to do so.

"The airport remains open and is operating three-quarters of scheduled flights," Heathrow said in statement. "Before coming to the airport, passengers must check their flight status with their airline."

National Rail said poor weather conditions are affecting travel across England and Wales. Trains on Chiltern Railways, CrossCountry, Great Western, and Virgin Trains are also being affected by delays.

Associated Press