Snow ploughs and gritters are on standby as the UK prepares to be engulfed by snow.

Forecasters are predicting that up to 20cm may fall in some areas as icy winds and heavy snow rolls in from Russia overnight.

Southeast England and the Pennines are expected to bear the brunt of the weather but much of the UK will see heavy snow over the next 48 hours.

Gatwick and London City airports were forced to close their runways temporarily to clear ice and snow from the tarmac, airport operators said.

The morning and evening rush hours are expected to be disrupted, with snow causing problems on the transport network.

The Met Office issued an extreme weather warning for London and southeast England as the lowest temperatures for 13 years were recorded.

Temperatures plummeted steadily today as the freezing easterly winds that herald the snow increased. By 6pm on Sunday parts of Kent were blanketed with snow and stretches of the London-bound M20 were closed because of treacherous conditions.

By midnight tonight the flurries are expected to give way to heavy prolonged snowfall, resulting in much of the UK waking to a blanket of snow.

A spokesman for MeteoGroup said: "We are in for a significant, disruptive snowfall event. Large parts of the UK will wake up to snow tomorrow with some areas seeing up to 20cm."

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