LONDON (AP) — Scores of travelers are suffering from flight disruptions as freezing fog caused delays and cancellations at London airports ahead of Christmas.

Forecasters at the Met Office have issued a severe weather warning for southern and central England and some parts of Wales until Tuesday.

British Airways said freezing fog across parts of Britain and northern Europe caused disruption to its short-haul schedule Monday. The airline cancelled at least 49 departing and 49 arriving flights at London's Heathrow Airport.

Heathrow said a small number of flights were cancelled in advance due to poor visibility. Gatwick and London City also saw disruptions.

At Manchester Airport, no flights were able to take off or land for several hours Monday as one runway was shut due to fog and another was closed for maintenance.