lol, i know it hisses it down up with you in Scotland, not much better in Wales m8, this does work trust me, and rain won't put the candle out unless its hammering down and then most won't have birds out even up with you. I found an alternative is to use them laser pens you can buy with petrol, they have them that flash several miles into sky, I made them waterproof and pinned them on shed and leave them flash when hawks come. I have fancy birds including some insane tumblers who have 'eat me' on their heads and they haven't been jumped on since using this. Never going to say the methods are going to be foolproof, but its an option.
garage by me stopped selling them now but i have one i'll take a photo of and will upload it here so you can see if you can get same, worth a try.