I just did one too and took virually all day to shoot three dresses after it took 2 hours for hair and make up.
Outside at this time of year is well and truly dodgy unless it's demo stock and they don't mind the cleaning bill!
Wind and rain won't do an awful lot for the images unless you are going for windswept and interesting

I can see the scope for Irish Coast image shot with BIG flash but that's honestly not the best way to show off the dresses. The dressmakers usually want to see detail and that means good fashion lighting.