How many days until spring?

When does spring start?

Astronomical spring in the Northern Hemisphere begins at the March equinox, usually on March 19, 20 or 21, and lasts until the June solstice. Meteorological spring, used by weather services, runs from March 1 to May 31. In the Southern Hemisphere, the March equinox marks the start of autumn.

The spring equinox

"Equinox" comes from Latin for "equal night". At the equinox the Sun is directly above the equator, and day and night are roughly equal in length all over the world. In practice daylight is slightly longer than 12 hours on the equinox, because the Sun's disc is visible before its center rises and the atmosphere bends its light. After the March equinox, days in the Northern Hemisphere keep getting longer until the summer solstice.

The equinox is an exact moment, and because the calendar year (365 days) doesn't match the solar year (about 365.24 days), the moment shifts by about six hours each year, resetting every leap year. That's why the first day of spring can fall on different dates.

Spring festivals

• Nowruz: the Persian New Year, celebrated at the March equinox by around 300 million people in Iran, Central Asia and beyond.
• Easter and Passover: both are timed by the spring full moon. See Easter and Passover.
• Holi: the Hindu festival of colors, celebrated at the full moon in February or March.
• Cherry blossom season: hanami in Japan and the National Cherry Blossom Festival in Washington, D.C.
• Chichén Itzá: at the equinox, the setting sun creates the shadow of a serpent descending the steps of the El Castillo pyramid in Mexico.

Signs of spring

Daylight saving time begins in the US a couple of weeks before the equinox (see DST starts), migrating birds return, and flowers such as crocuses and daffodils appear. It's also the traditional season for spring cleaning, gardening and, in many school calendars, spring break.