From Glossary of Meteorology


With respect to weather, generally descriptive of pleasant weather conditions, with due regard for location and time of year.

It is subject to popular misinterpretation, for it is a purely subjective description. When this term is used in weather forecasts (National Weather Service), it is meant to imply 1) no precipitation; 2) less than 0.4 sky cover of low clouds; 3) no other extreme conditions of cloudiness, visibility, or wind; 4) unrestricted visibility; and 5) light winds of generally less than 10 knots (5 m s-1).
Compare cloudy.