Seasons

Seasons Diagram

Earth experiences four seasons: spring, summer, fall, and winter. This happens because our planet is tipped on its axis and the two poles point to the same directions in space all year. Summer occurs on the hemisphere that is tipped toward the Sun. The hemisphere tilted away from the Sun experiences winter.

Our seasonal weather depends on where we live. Earth’s distance from the Sun has very little effect on the seasons.

SpringSummer FallWinter
2016
Spring equinox 9:30 p.m. PDT March 19
Summer solstice 3:34 p.m. PDT June 20
Autumn equinox 7:21 a.m. PDT September 22
Winter solstice 2:44 a.m. PST December 21
2017
Spring equinox 3:29 a.m. PDT March 20
Summer solstice 9:24 p.m. PDT June 20
Autumn equinox 1:02 p.m. PDT September 22
Winter solstice 8:28 a.m. PST December 21
2018
Spring equinox 9:15 a.m. PDT March 20
Summer solstice 3:07 a.m. PDT June 21
Autumn equinox 6:54 p.m. PDT September 22
Winter solstice 2:23 p.m. PST December 21
2019
Spring equinox 2:58 p.m. PDT March 20
Summer solstice 8:54 a.m. PDT June 21
Autumn equinox 12:50 a.m. PDT September 23
Winter solstice 8:19 p.m. PST December 21
2020
Spring equinox 8:50 p.m. PDT March 19
Summer solstice 2:44 p.m. PDT June 20
Autumn equinox 6:31 a.m. PDT September 22
Winter solstice 2:02 a.m. PST December 21
2021
Spring equinox 2:37 a.m. PDT March 20
Summer solstice 8:32 p.m. PDT June 20
Autumn equinox 12:21 p.m. PDT September 22
Winter solstice 7:59 a.m. PST December 21
2022
Spring equinox 8:33 a.m. PDT March 20
Summer solstice 2:14 a.m. PDT June 21
Autumn equinox 6:04 p.m. PDT September 22
Winter solstice 1:48 p.m. PST December 21
2023
Spring equinox 2:24 p.m. PDT March 20
Summer solstice 7:58 a.m. PDT June 21
Autumn equinox 11:50 p.m. PDT September 22
Winter solstice 7:27 p.m. PST December 21
2024
Spring equinox 8:06 p.m. PDT March 19
Summer solstice 1:51 p.m. PDT June 20
Autumn equinox 5:44 a.m. PDT September 22
Winter solstice 1:20 a.m. PST December 21
2025
Spring equinox 2:01 a.m. PDT March 20
Summer solstice 7:42 p.m. PDT June 20
Autumn equinox 11:19 a.m. PDT September 22
Winter solstice 7:03 a.m. PST December 21

The Reason for Seasons

Seasons Diagram

The Summer Sun

Summer Sun DiagramDuring the summer months, the Sun’s position in the sky brings warm weather, long days, and short nights. Earth’s surface and atmosphere warm up because they receive more heat from the Sun.

In summer, the Sun appears high in the sky and is up longer. Its light falls to the surface at a very steep angle on the half of Earth that is tipped toward the Sun.


The Winter Sun

Winter Sun DIagramIn the winter, the Sun’s position in the sky brings cooler weather, with short days and long nights. Earth’s surface and atmosphere cool down because they get less heat from the Sun.

The winter Sun appears low in the sky during the day on the half of Earth that is tipped away from the Sun. Sunlight streams to the surface at a very shallow angle.