Snow and Cold Bring Parts of U.K. to a Standstill

LONDON — A coating of snow and ice on Sunday upended travel in Britain and put increased pressure on the country’s energy supplies, already under strain from a prolonged cold snap.

The winter weather intensified on Sunday as a foggy afternoon turned into a snowy evening across much of the country, with a few inches of snow in places continuing into early Monday. Temperatures in parts of Britain, especially in London and other areas in the south, are not often cold enough for snow, making each infrequent occurrence a delight for the eyes but a headache for transit.

But the past week has seen plenty of snow-ready frigid temperatures, with more expected in the week ahead.

As snow dusted the country on Sunday, flights were canceled from London to Glasgow, with some airports, including Gatwick and Stansted in London, briefly closing their runways on Sunday night to clear snow. The delays continued into Monday as airlines worked through backlogs of canceled flights amid continued freezing weather.

Some rail lines also reported weather-related delays.

The Met Office warned that fallen snow and icy patches would continue to create hazardous conditions for drivers and cyclists in parts of southern England, including London, into Tuesday. Further north, in parts of Scotland and northern England, travel disruptions are likely to continue into Thursday.

Britain had already endured a week of frigid temperatures, with more below-freezing lows expected. A Level 3 cold weather alert is in place for much of England until Friday. The authorities have advised people to check in on vulnerable friends and family to ensure they have access to warm food and drinks and are able to heat their homes.

In Solihull, outside Birmingham, on Sunday, three boys, aged 8, 10 and 11, died after falling into an icy lake, the West Midlands Police said on Monday. A fourth boy, 6, remains in critical condition in a hospital, the police said.

An investigation is continuing to determine “exactly what happened and if anyone else fell into the water,” the police said.

The extended cold streak has put extra stress on energy supplies. The National Grid, which operates Britain’s electricity system, warmed up two contingency coal plants to “give the public confidence in Monday’s energy supply,” it said in a statement. It said it would not necessarily use the extra units, but that they were available if needed.

In Britain, snow is on the ground for an average of 15.6 days per year, according to the Met Office.