State of the atmosphere at a particular place during a short period of time. It involves day-to-day changes in such atmospheric phenomena as temperature, humidity, precipitation (type and amount), air pressure, wind, and cloud cover. Most weather occurs in the troposphere, but phenomena of the higher regions of the atmosphere, such as jet streams, and geographic features, most notably mountains and large bodies of water, also affect it. See also climate.

This entry comes from Encyclopædia Britannica Concise.
For the full entry on weather, visit

Seen & Heard

What made you look up weather? Please tell us what you were reading, watching or discussing that led you here.