There was further disruption at Bournemouth and Cardiff airports, while road and rail services were hit by freezing temperatures meaning many travellers were unable to complete their journeys.
Flights were suspended at Bristol at around 10.30pm on Thursday night so snow could be cleared from the runway, taxiways and aircraft stands, said the airport in a tweet.
However, as the conditions worsened overnight, and despite efforts by airport staff to keep the airfield clear, the airport remained shut on Friday morning.
In an update issued at 6.30am, the airport said: “Our teams have been working through the night to clear snow from the airfield. Snow is still falling and the airfield remains closed until 8am.
“Please monitor our social media feed for a further update and contact your airline for specific flight queries.”
The closure has since been pushed back to midday.
The BBC reports more than 35 flights have been cancelled at Heathrow, including dozens of British Airways flights.
Bournemouth airport confirmed at around 6.15am it was closed due to snow. An update on operations is due at 9am.
Cardiff airport also experienced disruption overnight, with passengers advised to check live flight information before travelling, and/or contact their airline.
Heathrow Express, Gatwick Express and Stansted Express were all operational on Friday morning, although passengers were advised to check before travelling and to take care when using stations.
Stansted and Luton airports confirmed they were operational as usual.
