| Season | Astronomical Start | Meteorological Start | | :--- | :--- | :--- | | | September 22 (Vernal Equinox) | September 1 | | Summer | December 21 (Summer Solstice) | December 1 | | Autumn | March 20 (Autumnal Equinox) | March 1 | | Winter | June 21 (Winter Solstice) | June 1 |
Example (Northern Hemisphere, typical year)
The Earth takes time to heat up and cool down. Even though the summer solstice (maximum sunshine) is June 21, the warmest temperatures usually happen in July, which is why meteorological summer includes the whole months of June, July, and August.
The confusion is understandable. There isn't just one universal answer to the question, In fact, scientists, meteorologists, and astronomers use two very different systems to define the seasons. when do the four seasons start and end
The winter solstice has the fewest hours of daylight. The North Pole is tilted farthest from the sun. Ironically, this is when the "cold season" officially begins astronomically, even though many locations have already experienced freezing weather.
Starts at the Summer Solstice (June 20 or 21) and ends at the Autumnal Equinox (September 21, 22, or 23). Meteorological Summer: Starts June 1 and ends August 31.
| Season | Start (Solstice/Equinox) | Typical Start Date | End Date | | :--- | :--- | :--- | :--- | | | Vernal Equinox | March 20 | June 21 | | Summer | Summer Solstice | June 21 | September 22 | | Autumn | Autumnal Equinox | September 22 | December 21 | | Winter | Winter Solstice | December 21 | March 20 | | Season | Astronomical Start | Meteorological Start
Neither is "better," they just serve different purposes. Everyday people and calendar publishers usually refer to the astronomical dates. However, weather channels, agricultural planners, and climate scientists exclusively use meteorological dates because uniform months make it easier to compare weather patterns from year to year.
These are defined by equinoxes and solstices. They usually fall around the 20th–22nd of the month. March 20 – June 20 (Spring Equinox) Summer: June 21 – September 21 (Summer Solstice) Autumn: September 22 – December 20 (Fall Equinox) Winter: December 21 – March 19 (Winter Solstice) 🌡️ Meteorological Seasons
The Earth takes roughly 365.24 days to travel around the sun, but our calendar is 365 days. To fix this drift, we add a leap day every four years. This correction causes the exact time and date of the astronomical equinoxes and solstices to flip between days. There isn't just one universal answer to the
Tropical and monsoon climates
For the year 2026, the specific astronomical transitions are as follows: Northern Hemisphere (Astronomical) Southern Hemisphere (Astronomical) March 20 – June 20 September 23 – December 21 June 21 – September 21 December 22 – March 19 (2027) September 22 – December 20 March 20 – June 20 December 21 – March 19 (2027) June 21 – September 22 Two Ways to Define Seasons Astronomical Seasons : These are defined by (when day and night are roughly equal) and
It is a common misconception that the seasons "shift" by six months everywhere. They do. If you are reading this in Sydney, Australia, or Cape Town, South Africa, you must invert the dates.