Can you please explain a "fair weather day"? What are the conditions that make up a "fair" day?

MIKE MOSS SAYS:     The term "fair" is a somewhat subjective one when it comes to general weather descriptions, more or less meaning pleasant weather with few extremes, given the time of year. In a more specific sense, the word "fair" may be used in a National Weather Service forecast or observation when less than 3/8 of the sky is covered by opaque clouds, there is no precipitation, visibility is unlimited, and there are no extremes of temperature or winds (usually meaning that it is not abnormally cold or warm for the season and time of day and that winds are about 10 knots or less).