Northern Hemisphere seasons:

The naming of the seasons puts the Equinoxes of the Solstices at the beginning of their respective seasons. In the Northern Hemisphere, for example, the sun is lowest in the sky when it is directly over the Tropic of Capricorn (in the Southern Hemisphere), so this day would be the beginning of Winter, and hence this would be the day of the Winter Solstice for the Northern Hemisphere. Autumn/Fall always occurs as Summer ends and before Winter begins; Spring occurs after Winter and before Summer. In the Southern Hemisphere, because the sun is highest/lowest in the sky in the opposite sense as in the Northern Hemisphere, the seasons are "reversed" for the same dates in the Northern Hemisphere. Thus, Winter begins on June 21 (and so this would be the day of the Winter Solstice for the Southern Hemisphere) and Summer begins on December 21; the Autumnal and Vernal Equinoxes are reversed from those in the Northern Hemisphere.