Positive in clear water where they can normally see you. None to negative in muddy water. I can usually catch them either way but sometimes when it is real windy or heavy they turn off. Light to medium rain doesn't do much though.
This is just IME
_________________________
-Mason
Fish of 2008 Bass- 1 Buffs- 4 Goo's- 1 Perch- ~100
Agree w/Mason about rain, but would add that in my experience they definitely bite better during low light conditions....early, late, and cloudy days. Bright sunshine kind of turns them off and does send them down. Probably an instinctive reaction to protection from predators which can see them much easier on bright days.