Mate basically any time form mid- Sept onwards. Mid- Oct onwards is best, if you could do last 2 weeks of Oct (as in stay there for 14 days) you should be sweet, seabreezes are settled in and there is still some swell around hopefully
If you surf also you'll always be happy up there.
i surf there between june-july...it hasn't been windy there when i surf up there & + i'm a youngen!!!