SEATTLE — Even a clear sky contains layers of wet and dry air, that is, layers with different humidities. You can’t see these layers unless the humidity is high enough for the moisture in the layer to ...

Answer: Clouds form when sufficiently moist air is cooled to the dew point temperature of the air or below, so that either liquid water droplets form on cloud condensation nuclei, or in the case of ...

Have you ever looked up at the clouds in the sky and wondered how they form? Understanding cloud formation is really important for studying weather patterns and making accurate forecasts. Those clouds ...

Alexandria Johnson does hard science on the most nebulous of subjects: clouds. As an atmospheric scientist and assistant professor of practice in Purdue University’s College of Science, she studies ...

Clouds need two essential ingredients to form, and both must be present simultaneously for the process to begin. There are two ingredients needed for clouds to form: water and nuclei. The first ...

Alexandria Johnson does hard science on the most nebulous of subjects: clouds. As an atmospheric scientist and assistant professor of practice in Purdue University’s College of Science, she studies ...

With a ceiling set at 3000 feet, all the clouds confined to that limited altitude, flying above it reveals the possibility of encountering another layer or no clouds at all. Why do clouds stratify at ...

Have you ever wondered how a cloud stays in the sky? In a recent conversation with my friend and colleague Alan Sealls, the AMS President-Elect told me that he pondered this very question, and it ...