It is the third day of successive fog although flights were also cancelled before Christmas because of visibility issues.
She said: "Early morning flights have been affected by the fog, but we're hoping this won't have a widespread effect on later flights".
Meanwhile a multi-vehicle collision on the Bangor-bound A2 Sydenham Bypass close to City Airport is causing significant delays.
Irish passengers flying to airports in the south of England from Ireland have had their plans disrupted.
A dense fog led to delays, and the cancellation of at least one incoming flight.
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Green, 26, posted a Snapchat video late Thursday night that showed him walking toward a private jet on the Oakland airport runway. Though they still trailed by 13, this was a very different team than which had surrendered so meekly in the first half.
Some flights from Belfast International and Belfast City Airport to London are delayed or cancelled due to freezing fog in England.
Today, Heathrow, Gatwick and City Airport are all urging passengers to check the status of their flights before making any journey to the airport.
British Airways said in a statement: "For safety reasons, air traffic control has to allow greater space between landing aircraft in fog or during periods of low visibility, and this will mean a reduced number of aircraft being allowed to land each hour".
However, other airports were less affected by the fog, with flights at Gatwick, Stansted and Luton all reporting normal conditions.
Spokesman Ian Crowder said on Thursday: "We have got the worst possible conditions really, of fog and icy roads, and that can be lethal".