I got really lucky when I was there. It was bright and sunny every day except one. It ws strange. We were all kind of stunned. We're like, "Hey, WTF, isn't it supposed to rain?"
It was cool as well. Which was nice, at least to me. We went in June, and I wore the light coat I brought several times. It was really windy when we were in Scotland.
That's just my personal experience, I can't speak for year-round British weather.
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And while the seagulls are crying,
We fall but our souls are flying.