How is the dew point used for weather forecasting? Mike Moss: Dew point is of great interest to meteorologists because it is a very basic measure of the state of the atmosphere in terms of how much ...

Dew point/relative humidity questions come up fairly often and this is a good one. Water vapor in the atmosphere is pretty important for deep-sky observing and photography. The atmosphere can only ...

I've long wondered whether dew point or relative humidity is more important for good seeing. Which would be better: a cool night with lower dew point but higher humidity, or a warm night with higher ...