LONDON — Thick fog has caused numerous flight delays and cancellations at London Heathrow and other area airports.

Travellers were advised Monday to check their flight status before going to the airport after roughly 100 flights were cancelled and many more were delayed.

The Met Office forecasting service said visibility at Heathrow had been reduced to roughly 100 metres, leading to an overall slowdown in operations.

It issued a severe weather warning for London and most of southern England as driving conditions were also hazardous and slippery.

Conditions at Gatwick, London City and Stansted airports were also difficult with limited visibility.