The Met Office has placed London and Essex on an amber weather warning.
Around five to ten centimetres of snow is expected to fall across the region later today.
An amber warning is the second most serious weather warning and the Met Office warns that disruption to normal daily routine is to be expected.
Transport for London is advising people to check before they travel to ensure bus, tube and rail services are running.
And the London Fire Brigade is urging people to take extra care and not to take unnecessary risks as the cold weather takes its grip.
The Brigade’s Third Officer, Dave Brown, said: "These freezing conditions can cause us a headache as people take risks that they wouldn’t normally.
"Our advice is simple: stay off frozen ponds, lag your pipes to prevent your home from flooding, and be extremely careful with electric heaters to prevent fires."