I was there this time last year, I went for a 10 day trip and we had a bout 3 days of rain. Apparently this was totally out of character for the time of year (the ever nice locals kept apologising for the weather!), but actually it was fine, on some days it meant you could climb later in the day, at crags that would have otherwise been too hot in the sun.
I reckon you'll be reet! enjoy!