When does spring start?
Published by: Almanac
When does spring start? In 2023, the official first day of spring is Monday, March 20. This date marks the “spring equinox” in the Northern Hemisphere. What IS the spring equinox and is it always on the 20th? Before you try to balance that egg, read on to learn more—plus, enjoy ideas on celebrating the season!
When Is the First Day of Spring 2023?
In 2023, the March equinox happens on March 20, at 5:24 P.M. EDT. This falls on a Monday and is the astronomical beginning of the spring season in the Northern Hemisphere and the autumn season in the Southern Hemisphere.
If you thought that the spring equinox only ever occurred on March 21, you may be dating yourself. The civil calendar date of the equinox continues to shift every year.
What Is the Spring Equinox?
In the Northern Hemisphere, the spring equinox in the Northern Hemisphere (also called the March equinox or vernal equinox across the globe) occurs when the Sun crosses the celestial equator going south to north. It’s called the “celestial” equator because it’s an imaginary line in the sky above the Earth’s equator. Imagine standing on the equator; the Sun would pass directly overhead on its way north.
On the March equinox, the Northern Hemisphere and Southern Hemisphere receive roughly equal amounts of sunlight; neither hemisphere is tilted more toward or away from the Sun than the other.
Although in most locations (the North Pole and the Equator being exceptions) the amount of daylight had been increasing each day after the winter solstice, after the spring equinox, many places will experience more light than darkness in each 24-hour day. The amount of daylight each day will continue to increase until the summer solstice in June, during which the longest period of daylight occurs.
Here’s an interesting fact: Equinoxes are the only two times each year that the Sun rises due east and sets due west for all of us on Earth! While the Sun passes overhead, the tilt of the Earth is zero relative to the Sun, which means that Earth’s axis neither points toward nor away from the Sun.
What Does “Equinox” Mean?
The word equinox comes from the Latin words for “equal night”—aequus (equal) and nox (night). On the equinox, the length of day and night is nearly equal in all parts of the world.
Astronomically speaking, the first day of spring is marked by the spring equinox, which falls on March 19, 20, or 21 every year. The equinox happens at the exact moment worldwide, although our clock times reflect a different time zone. And, as mentioned above, this date only signals spring’s beginning in the Northern Hemisphere; it announces fall’s arrival in the Southern Hemisphere.
Interestingly, due to time zone differences, there isn’t a March 21 equinox in mainland U.S. during the entire 21st century! We won’t see a March 21 equinox again until 2101.
Some Ideas on How to Celebrate Spring!
Here are some ideas for how to spend the first week of spring.
- Get outside! Look around. Are worms and grubs reappearing? (The March Full Moon is called the “Worm Moon” for this very reason!)
- Watch the arc of the Sun across the sky as it shifts toward the north. Birds are migrating northward, along with the path of the Sun.
- Are daffodils poking up their heads? Trees, shrubs, and flowers are sensitive to temperature and day length, too! Since ancient days, people have used natural events as indicators of when the weather is right for planting.
- Can you feel the Sun getting stronger? The longer days bring high temperatures. Both we and the animals around us discard our warm clothes and heavy coats!