When Is the Spring Equinox?

March 19, 20, or 21 – the spring equinox date lands somewhere in that window depending on the year. When is the spring equinox in a specific year is a question with an answer measured in UTC, down to the minute, not a date circled on a wall calendar.

What Happens During the Spring Equinox?

El Castillo at Chichén Itzá was built around 1000 AD with its staircase angles calculated to produce one specific visual effect on two days a year: the equinoxes. Shadow and light fall across the steps in a way that traces the outline of a descending serpent. The pyramid functions as an astronomical instrument.

On equinox day, the sun rises due east and sets due west – at every location on Earth, without exception. That alignment holds on no other date. The equinox itself lasts a second: in 2026 it occurred at 14:46 UTC on March 20.

Day and night aren't actually equal on that day, though. The equilux – the date of true equal split – arrives a few days earlier. Atmospheric refraction pushes sunlight over the horizon before the sun geometrically reaches it, adding several minutes of daylight beyond the theoretical twelve hours.

Why Does the Spring Equinox Date Change?

Pope Gregory XIII didn't reform the calendar in 1582 out of preference – the Julian system had accumulated an 11-minute annual error since 46 BC, and by the 16th century the date of spring equinox had drifted 10 full days away from where the Church needed it for calculating Easter. The Gregorian fix dropped certain leap years to pull the equinox back into March and keep it there.

It didn't solve the problem completely. Earth's orbit takes roughly 365.25 days, not 365 – and no calendar divides that cleanly. The leftover fraction is why the equinox moves between March 19, 20, and 21 from one year to the next. The range is narrow, but the date never settles on one fixed point.

Spring Equinox in the Northern Hemisphere vs Southern Hemisphere

More than 300 million people celebrate Nowruz – the Persian New Year – at the exact moment of the spring equinox. The celebration is 3,000 years old and begins precisely when the equinox occurs, not on a fixed calendar date. That level of astronomical precision, maintained across millennia, reflects how central the March equinox has been to cultures across the spring equinox northern hemisphere and Central Asia.

Japan marks the same moment as a national public holiday – Shunbun no Hi, part of a seven-day period called Haru no Higan dedicated to honouring ancestors. Both traditions exist in the Northern Hemisphere because March signals spring there. Cross into the Southern Hemisphere and the same astronomical instant carries a different meaning: autumn begins, days start shortening, and no spring festival marks the date.

Check MeteoFlow to monitor seasonal weather changes and daylight conditions as spring approaches.

Spring Equinox Time and Upcoming Dates

The 2026 equinox is already behind us. When was the spring equinox 2026? March 20, at 14:46 UTC – a moment that arrived and passed while most of Europe was mid-afternoon and North America was still in the morning.

The spring equinox time is always expressed in UTC because the event is simultaneous worldwide, but the local date shifts by time zone. Spring equinox 2028 falls on March 20 at 02:17 UTC – early enough that North American clocks still read March 19. Spring equinox 2030 arrives on March 20 at 13:51 UTC, landing comfortably within the same calendar date across most of the world.

Spring Equinox vs Meteorological Spring

March 1 and March 20 – two different answers to the same question about when spring begins. Meteorologists use the fixed date; astronomers use the equinox. The meteorological definition was created specifically for climate records, using clean three-month blocks that make long-term data easier to compare.

In 2026, meteorological spring started 19 days before the astronomical equinox. The two systems can diverge by nearly three weeks depending on the year. Neither is wrong – they're built for different purposes. One tracks the sun's position; the other tracks temperature records.

Use MeteoFlow to follow spring weather patterns and important astronomical dates throughout the year.

FAQ

Is day and night exactly equal on the spring equinox?

Not quite. The truly equal split – called the equilux – falls a few days before the equinox. Atmospheric refraction bends sunlight over the horizon, adding several minutes of daylight beyond the theoretical 12-hour mark.

What is the difference between the spring equinox and the vernal equinox?

Same event, two names. Vernal comes from the Latin ver, meaning spring – it's the older, more formal term used in astronomy and historical texts. Spring equinox says the same thing in plain English. Both refer to the March moment when the sun crosses the celestial equator moving northward.

Does the spring equinox affect weather?

Not directly. The equinox marks an orbital position, not a temperature threshold. Weather responds to accumulated seasonal warming over weeks and months – the thermometer doesn't reset on March 20.

Why is the spring equinox different in the Southern Hemisphere?

Geography determines what March 20 means for you. Above the equator, days are getting longer from that point. Below it, the same astronomical instant tips into autumn – nights start gaining ground, temperatures begin their seasonal descent. The sun's position is identical for everyone; what changes is which direction your hemisphere is heading.