When does summer start? Mark your calendars for the longest day of the year in 2024

Once daylight saving time begins and spring ushers in warmer temperatures and floral blooms, many are already eager to skip right to summer.

While many consider Memorial Day to be the unofficial start of summer, the season does not begin for about another month after the holiday. So, there's still time to prepare your backyard barbecue menu and stock up on sunscreen for the family's beach vacation.

Grab your calendar and a pen, it's time to mark down the first day of summer.

When is the first day of summer?

This year, the first day of summer, also known as the summer solstice, is Thursday, June 20. The true solstice will arrive in the Northern Hemisphere at exactly 4:51 p.m. EST. 

What is the summer solstice?

The summer solstice marks the longest day of the year. During the summer solstice, the Sun is at its highest point in the sky and the Earth's tilt toward the star is at its maximum, according to the National Weather Service.

In the U.S., at latitudes of approximately 40 degrees North, daylight during the summer solstice will last for about 15 hours, Space.com reports.

As the days go by, the amount of sunlight will decrease. This culminates with the winter solstice or the shortest day of the year. On the winter solstice, the Earth's tilt is its farthest from the Sun.

What are the summer months?

In the northern hemisphere, summer spans from the end of June to the end of September. On Sept. 22, the autumnal equinox marks the start of fall.

When is Memorial Day weekend?Here's when the holiday falls in 2024 and why its celebrated

What are the dates for the four seasons in 2024?

• First day of spring: March 19, 2024
• First day of summer: June 20, 2024
• First day of fall: Sept. 22, 2024
• First day of winter: Dec. 21, 2024

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