When is spring 2024? What to know about the vernal equinox as we usher in a new season

Ready or not, the spring season is almost here.

Tuesday, March 19 marks the vernal equinox, bringing the first day of spring to the Northern Hemisphere. Daylight hours will continue to increase, especially after the start of daylight saving time, and will peak with the summer solstice in June.

Millions of Americans will have the chance to experience another astronomical event soon after the spring equinox, with the solar eclipse on April 8 and a 115-mile-wide path of totality that will pass over portions of Mexico and the United States, ending in Canada. 

Here's what to know about the vernal equinox, and when the spring season will officially start for half the world.

Great North American Eclipse of 2024:When and where can I see it? What to know about the path of totality

When is the first day of spring in 2024?

The spring equinox is Tuesday, March 19 and brings the first day of astronomical spring to the Northern Hemisphere.

While the date for the vernal equinox and astronomical spring may shift a few days year to year, meteorological spring began a few weeks earlier and is always on March 1.

In the Southern Hemisphere, March 19 will mark the start of the fall season.

What is the exact time of the spring equinox?

This year, the spring equinox will happen for the Northern Hemisphere on Tuesday, March 19 at 11:06 p.m. EDT, according to the National Weather Service.

What happens during the spring equinox?

Seasons are caused by the Earth's tilt and rotation, which is on a tilted axis of 23.5 degrees, on average.

As the Earth orbits elliptically around the sun, it is at its closest point in January and the farthest in July. Near the summer solstice, which typically occurs around June 21, the Northern Hemisphere is in a more direct path of the sun's energy, producing longer days and shorter nights. 

Ninety days after each equinox in the summer and winter, the sun is positioned directly over the equator, which comes on or around September 21 in the fall and March 21 in the spring.

This year, the Earth is at the vernal, or spring, equinox on March 19.

"Basically, the sun's energy is in balance between the northern and southern hemispheres," the National Weather Service notes.

What does 'equinox' mean?

The word "equinox" is derived from the Latin words "aequus," meaning equal, and "nox," meaning night, according to the National Weather Service.

When is the summer solstice in 2024?

The summer solstice, or the day with the longest daylight hours of the year, will happen on June 20, 2024. It marks the start of the summer season in the Northern Hemisphere and the winter season in the Southern Hemisphere.

When was daylight saving time?

The clocks for millions of Americans sprang forward as daylight saving time began Sunday, March 10 at 2 a.m. local time, allowing for more daylight in the evening.

We lose an hour in March to gain more daylight in the summer evenings. When we "fall back" in November, it's to add more daylight in the mornings.