I always find it totally amazing how Dublin seems to have such a massive failure when they get the slightest gust of wind. I'm originally from the North Coast and we get significantly higher winds than this - think 60/70mph several times a winter and life goes on.
Belfast airport never seems to shut down because of wind and I'm pretty sure the wind will be higher there.
Derry also managed to have all it's Ryanair flights operating as normal today.
It's a little odd I have to say. 40 mph gusts are nothing to me, they really don't suggest a total shutdown of an entire airport.