Countdown to
The First Day of Spring
Winter lets go and the light comes back
Today is the First Day of Spring.
138 days until the First Day of Spring, on Saturday, March 20, 2027.
The First Day of Spring is Saturday, March 20, 2027. Happens the March (spring) equinox (computed astronomically, in UT).
The first day of spring is the day the Northern Hemisphere officially trades winter for the growing season. Astronomically it is the March equinox: around March 20 the Sun crosses the celestial equator heading north, daylight overtakes darkness, and the calendar turns toward warmth, planting, and renewal. It is the start of astronomical spring — the point from which the days keep lengthening all the way to midsummer.
Unlike a fixed holiday, spring does not begin on a set square of the calendar. It begins at an astronomical moment, which is why the date drifts a little from year to year and why “the first day of spring” is really the first day the season is measured from.
How we get this date. The countdown is pinned to the exact instant of the March equinox, computed from Jean Meeus’s Astronomical Algorithms (Ch. 27) and expressed in Universal Time. Spring officially begins the moment the Sun’s center crosses the celestial equator going north. Because the calendar year runs about a quarter-day longer than 365 days, that instant slips roughly six hours later each common year and snaps back with every leap day, so the first day of spring lands on March 19, 20, or 21 — most often the 20th in our era.
Not everyone starts spring here. Meteorologists open the season on March 1, grouping March, April, and May into a tidy three-month block that lines up with the temperature cycle and makes climate records easier to keep. The astronomical first day, tied to the Sun rather than the calendar, arrives about three weeks later.
A timezone note. Because the equinox is a single moment in Universal Time, the first day of spring can fall on different calendar dates around the world. When the crossing happens late on March 20 UT, it is still March 20 across the Americas but already past midnight — March 21 — in parts of Asia and the Pacific; and when it happens in the first hours of March 20 UT, it is still the evening of March 19 across the Americas. The astronomical instant is shared; the local date on the wall calendar is not.
For much of the world the day simply means lighter evenings, garden beds, and open windows. It also opens Nowruz, the Persian New Year, celebrated at the precise equinox by more than 300 million people, and it echoes through the spring festivals and rebirth imagery that run from Easter to Holi. However you greet it, the first day of spring is the calendar’s quiet promise that the light — and the growing season — is coming back.
🌷 Fun facts about the First Day of Spring
- Meteorologists start spring on March 1, so forecasters count the season as beginning about three weeks before the astronomical first day set by the equinox.
- The first day of spring is one of only two dates a year when the Sun rises due east and sets due west for nearly everyone on Earth.
- Thanks to time zones, the spring equinox has not fallen on March 21 anywhere in the mainland United States so far this century — and it will not again until 2103.
- Nowruz, the Persian New Year celebrated by more than 300 million people, is timed to the exact instant of the spring equinox.
- In the Southern Hemisphere the same March equinox is the first day of autumn, not spring.
Upcoming First Day of Spring dates
| Date | Days away |
|---|---|
| 138 days | |
| 504 days | |
| 869 days | |
| 1,234 days | |
| 1,599 days |
How people mark the First Day of Spring
- Welcoming Nowruz, the Persian New Year
- Starting seeds and planting gardens
- Spring cleaning and opening the windows
- Egg hunts and springtime festivals
- Watching the equinox sunrise at ancient sites
Frequently asked
When is the first day of spring?
In the Northern Hemisphere it is the March equinox, which falls around March 20 each year and can land on March 19 or 21. It marks the moment the Sun crosses the celestial equator heading north and daylight begins to outlast the night.
How is the date calculated?
The countdown is pinned to the exact instant of the March equinox, computed from Jean Meeus's Astronomical Algorithms (Ch. 27) and given in Universal Time — the moment the Sun's center crosses the celestial equator, not a fixed calendar date.
Is the first day of spring the same as meteorological spring?
No. Meteorological spring always begins on March 1 so climate records fall into tidy three-month blocks. The astronomical first day, tied to the equinox, arrives about three weeks later.
Why does the first day of spring change each year?
A calendar year is about a quarter-day longer than 365 days, so the equinox slips roughly six hours later each common year and jumps back with every leap day — which is why the first day of spring shifts between March 19, 20, and 21.