Transport for London said last night that no disruption to the Tube service was currently forecast, but conditions could change overnight.
London Overground trains were disrupted yesterday and are unlikely to operate normally today. Transport for London said tickets will be accepted on trains and buses on any reasonable route.
National Rail said the worst-hit lines – Southeastern, East Coast, ScotRail and services south of the Thames – will be treated tonight by “ghost trains” using anti-freeze to clear the routes.
A spokesperson said more than two-thirds of rail services nationwide ran on time yesterday, but that disruption today was “almost certain”.
Heathrow Airport said last night it was operating normally, but that some airlines were cancelling or delaying flights. London City airport cancelled a string of flights yesterday.
Gatwick closed its runway late last night to clear the snow and frost, and said it hoped to run services today.
Businesses are likely to face further absenteeism as hundreds of schools in the capital shut in the face of freezing weather.