Severe weather: Flights cancelled amid Gonzalo warning
Heathrow has said about 10% of flights will be cancelled on Tuesday, as strong winds are expected when the remnants of Hurricane Gonzalo hit the UK.
Flights with the 20 biggest carriers would be affected, it said.
British Airways (BA) said it had cancelled flights on Tuesday ahead of the expected severe weather.
The remains of the hurricane are predicted to bring heavy rain and gusts of up to 75mph in some areas, causing disruption to rush-hour travel.
The Met Office has issued "be aware" warnings, with gales forecast for much of the UK, while BBC Weather said heavy rain was already spreading across many areas.
The Met Office said the strongest winds were expected "after the rain clears and winds veer north-westerly through Tuesday morning".
Gonzalo caused widespread damage and a power blackout when it hit the island of Bermuda last week, with winds of up to 110mph.
The Met Office said the strongest winds would "coincide with the morning rush hour in places".
A Heathrow spokesman said: "There will be some cancellations, around 10% of flights are affected at Heathrow.
"We do not know exactly how many passengers or flights that will have an impact on, although the cancellations are only expected for tomorrow [Tuesday]."
BA said the "tail end" of the hurricane was "very likely to affect some flights in the UK and northern Europe throughout Tuesday".
It agreed to change its schedule after a request from Heathrow and the National Air Traffic Services.
"The forecast of poor weather has meant that, along with other airlines at Heathrow, we have made some proactive flight cancellations to give customers as much time as possible to be rebooked onto alternative flights," a spokesman said.
"We are sorry for any difficulties caused by the poor weather and will do all we can to minimise the effect it has on our operations."
Travellers are urged to check online to see if their flights were affected.
The Met Office said the remains of Gonzalo would "run eastwards across the Atlantic", bringing a period of strong winds and heavy rain to the UK.
"The strongest winds are expected on Tuesday as the low pressure clears eastwards," it said.
Forecasters added that fallen leaves could impede drainage, increasing the risk of surface water on roads and causing difficult driving conditions.
But the Met Office also said that such weather was not unusual for this time of year.
The yellow warning for high winds is in place for: Highlands & Eilean Siar; Orkney and Shetland; Grampian; Strathclyde; south-west Scotland; Lothian and Borders; Tayside and Fife; Northern Ireland; Wales; north-west and north-west England; Yorkshire and Humber; West Midlands; East Midlands; eastern England; south-west England; London and south-east England.