Summer Solstice 2027

The summer solstice of 2027 is on Monday, June 21, at 10:11 a.m. Eastern Time, which is 15:11 BST in the UK. It is the longest day of the year in the Northern Hemisphere and the start of astronomical summer. New York gets 15 hours 6 minutes of daylight that day, and London 16 hours 38 minutes.

When is the summer solstice in 2027?

The solstice is one moment for the whole world: 14:11 Universal Time on June 21, 2027, as calculated by the U.S. Naval Observatory. On local clocks that is:

The date is June 21 across the US and Europe. In the far east of Asia and in Australia and New Zealand the same moment falls late in the evening of June 21 or just after midnight on June 22.

How long is the longest day?

It depends on how far north you are. The table uses sunrise and sunset times for June 21, 2027 from the U.S. Naval Observatory; the last column is the time between them.

Times are local daylight time. The pattern is plain: the farther north, the longer the day. Edinburgh has almost four hours more daylight than Miami. Twilight adds usable light at both ends. In New York civil twilight starts at 4:52 a.m. and ends at 9:04 p.m.

The days on either side are almost as long. Around the solstice the length of the day changes by only seconds from one day to the next.

What happens at the summer solstice?

The Earth's axis is tilted by about 23.4 degrees. As the planet goes around the Sun, the Northern Hemisphere leans toward the Sun for half the year and away from it for the other half. The June solstice is the moment the northern lean is at its greatest.

On that day the Sun reaches its highest noon position of the year for places north of the Tropic of Cancer and stands directly overhead on the tropic itself, at 23.5 degrees north. A higher Sun stays above the horizon longer, which gives the long day and the short night.

The word solstice comes from the Latin solstitium, roughly "the Sun stands still." According to the Royal Observatory in Greenwich, the name describes how the Sun's seasonal movement north pauses before it turns back south.

South of the equator everything is reversed. June 21, 2027 is the winter solstice and the shortest day of the year in Australia, New Zealand, South Africa and most of South America.

Is the solstice the first day of summer?

There are two calendars. In the astronomical one, summer starts at the June solstice and ends at the September equinox, which in 2027 falls on September 23. Counted that way, the summer of 2027 lasts about 93.7 days and is the longest season of the year.

In the meteorological calendar, used by weather services, summer is simply June, July and August. It starts on June 1 and ends on August 31. All four turning points of the year are on our page about the equinoxes and solstices of 2027.

Why isn't the longest day the hottest?

The Sun delivers the most energy to the Northern Hemisphere around the solstice, but land, sea and air keep warming for weeks afterward. The Royal Observatory puts it simply: the oceans and the atmosphere lag behind, so the warm weather peaks later.

The National Weather Service gives an example from the Great Lakes. In northern Ohio the highest daily temperatures typically come about three weeks after the solstice, in mid-July, and in Cleveland both July and August are warmer on average than June.

The solstice is also not the day the Earth is nearest the Sun. The planet is at its farthest from the Sun in the first week of July. Seasons come from the tilt, not from distance.

How is the solstice marked?

The best-known gathering is at Stonehenge in England. The stones are aligned to frame the sunrise on the summer solstice, though it is not certain that this was their purpose. The solstice is one of the few occasions when visitors may walk right up to the stones, and many people come to watch the Sun rise.

Elsewhere, midsummer is simply the season of the longest evenings. In June 2027 it comes with a bright Moon: the Strawberry Moon is full on Friday, June 18, three days before the solstice, as shown in our full moon calendar for 2027.

Summer solstice dates for 2026, 2027 and 2028

The solstice comes about six hours later each year and jumps back when a leap day is added.