This Friday 20 March, at 10 a.m. spring has begun

This Friday 20 March, at 10 a.m. spring has begun 

Spring begins with the spring equinox, which usually falls on 20 or 21 March in the northern hemisphere. For example: It is often March 20. Some years it may be March 21 (very rarely March 19)

This 2026, spring begins on March 20 

The start day of spring varies because the year does not last exactly 365 days, but approximately 365.2422 days. This small lag is what makes the Spring Equinox not always fall on the same day.

To compensate: Every year there are about 6 hours "left".

These hours are accumulated: Every 4 years we add an extra day (leap year) in February. Even so, the adjustment is not yet perfect, and that is why the equinox may fall: March 19 (very rare), March 20 (the most common) or March 21.

In addition, small adjustments to the calendar and the actual movement of the Earth around the Sun also influence.

In short: it is not that spring changes, but that our calendar tries to follow a movement that is not exact.

Here are the approximate dates of the Spring Equinox (beginning of spring in the Northern Hemisphere) for the next few years:

2026 → March 20

2027 → March 20

2028 → March 20

2029 → March 20

2030 → March 20

2031 → March 20

2032 → March 20

2033 → March 20

2034 → March 20

2035 → March 20

As you can see, for many years in a row it falls on March 20, which is the most common today.

March 21, which used to be more common, now hardly occurs due to the adjustment of the calendar. March 19 can appear very punctually in some distant years.

Here is the approximate time of the Spring Equinox in Palma (Mallorca) for the coming years:

2026 → March 20 at 10:01 am

2027 → March 20 at 3:25 p.m.

2028 → March 20 at 8:17 p.m.

2029 → March 20 at 02:02 h

2030 → 20 March at 07:52 h

The time changes every year because the Earth does not take exactly the same time to complete each revolution of the Sun.

An interesting detail: the equinox is a very precise instant, not all day. It is the exact moment when the Sun crosses the celestial equator and day and night last practically the same all over the world.