Water vapor is more likely to merge onto atmospheric particulates when the relative humidity is high. Since warm air has much more water vapor in the air when the air is saturated as compared to cold air, the effect of haziness is especially evident on warm and humid days. Water vapor merging onto particulates makes them bigger and thus visibility gets reduced. Wind speed is a factor also. Stronger winds will loft more and larger particulates into the atmosphere which reduces the visibility. The visibility tends to be better on days that are cool, dry and have light wind. |