I would be curious to find the reasoning behing the ball flying further in humid consitions. It seems to but I can't reason why considering the air is heavier with moisture. Or is this a golfing urban legend?
When the air temp is high and the humidity is like a gas not moisture.
As KAPLOWD said, the air will be lighter and the ball will stay up there
longer. When it's really hot like 90* and humidity is high like 70, balls
will have a bit longer carry. If temps are low like 50* and the humidity
is high, the air becomes more dense and the ball will not go as far.
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