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 ...

Dew point and relative humidity, two terms that have floated around many weather forecasts over the years. What exactly do they mean and when are they best used to describe the conditions outside? Let ...

Dew point is the temperature at which the air becomes “saturated” – in other words, it is holding all the water vapor it possibly can. If the temperature and the dew point equal each other, the water ...

The heat index shows how humidity makes hot days feel hotter, and why direct sun can push dangerous conditions even higher.