Based on annual temperature cycles and calendar months.
The start of the seasons is determined by the Earth's tilt on its axis and its orbit around the Sun. The Earth is tilted at an angle of about 23.5 degrees, which means that as it orbits the Sun, different parts of the planet receive varying amounts of solar radiation throughout the year. This variation in solar radiation leads to the changes in temperature, daylight hours, and weather patterns that we experience as the seasons. when do the seasons start
The start dates of the seasons depend on whether you use the or meteorological calendar. While most people mark the seasons by solstices and equinoxes, meteorologists use a fixed, three-month schedule to make tracking weather data easier. 2026 Seasonal Start Dates (Northern Hemisphere) Astronomical Start (Equinox/Solstice) Meteorological Start (Fixed Date) Spring Summer Autumn September 22/23 September 1 Winter December 21 December 1 Understanding the Differences When Do the Seasons Start and End in 2026? Based on annual temperature cycles and calendar months
★★★★☆ (4/5) Clear and useful once you understand the three definitions, but poorly explained in most quick online searches. If you want one practical answer: use meteorological seasons for daily life, astronomical for tradition. This variation in solar radiation leads to the
The summer solstice features the most sunlight, but it is rarely the hottest day of the year. This delay is called seasonal lag. Earth’s massive oceans and landmasses take several weeks to absorb heat and warm up, pushing peak summer temperatures into July and August.
Based on observable natural events (first frost, blooming, leaf change) or solar longitude (e.g., traditional Chinese Lìchūn – spring starts around Feb 4). Examples: