If the Airline is knowingly operating from such an Airport then I would want to be advised it might sound DAFT but the Airline should not be able to just cancel a flight they should have a contingency plan.
And what happens on a foggy day at (the very well equipped) Heathrow - thats right, BA cancel a fair percentage of the short haul programme to protect the flying for days to come.
That's what EZY have done here, cancelled the first sector of the first wave to protect the flying programme later in the day. I should think they don't want and stragglers by the end of the day as its due to be widespread fog again to night.
DH