At mid-northern latitudes in the Northern Hemisphere, the earliest sunrises of the year happen around mid-June, despite the fact that the summer solstice – the year’s longest day – is still about a week away. And if you live at middle latitudes in the Southern Hemisphere, the earliest sunsets take place around now, even though the winter solstice – the year’s shortest day – isn’t for another week.
For those of you who are privileged enough to be outdoors before one of these early sunrises, you’ll find some of the most beautiful dawn twilights of the year.
The exact date of earliest sunrise varies with latitude. At 40o north latitude – the latitude of, say, Philadelphia in Pennsylvania – the earliest sunrise of the year will happen on June 14. For that same latitude, the latest sunset of the year will fall on or near June 27. This is in spite of the fact that the longest day of the year (in terms of daylight) comes on the June summer solstice.
So it is for other Northern Hemisphere latitudes. The dates of earliest sunrise and latest sunset do not coincide exactly with the solstice. Appreciably south of Philadelphia’s latitude, the earliest sunrise has already come and gone (in late May or early June) and the latest sunset occurs at a later date (sometimes as late as July). In Hawaii, for instance, the earliest sunrise precedes the June solstice by about 2 weeks, and the latest sunset comes about 2 weeks after. Farther north, the earliest sunrise and latest sunset happen closer to the June solstice. Check it out at your latitude, using links on our almanac page.
The earliest sunrises come before the summer solstice because the day is more than 24 hours long at this time of the year. In the Southern Hemisphere, the earliest sunsets of the year come before the winter solstice for the same reason.
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See full size | Sunrise over Currituck, North Carolina. Credit: GregDiesel Landscape Photography
In June, the day (as measured by successive returns of the midday sun) is nearly 1/4 minute longer than 24 hours. Hence, the midday sun (solar noon) comes later by the clock on the June solstice than it does one week before. Therefore, the sunrise and sunset times also come later by the clock, as the tables below help to explain.
For Philadelphia (40o north latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 5:31 a.m. | 1:01 p.m. | 8:31 p.m. | 14h 59m 23s |
| June 21 | 5:32 a.m. | 1:03 p.m. | 8:33 p.m. | 15h 00m 38s |
For Valdivia, Chile (40o south latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 8:12 a.m. | 12:53 p.m. | 5:34 p.m. | 9h 21m 54s |
| June 21 | 8:14 a.m. | 12:55 p.m. | 5:35 p.m. | 9h 20m 42s |
Source: timeanddate.com
Early sunrise in Sweden via Per Ola Wiberg
Early sunrise by Flickr user Raffee
Bottom line: The earliest sunrises of the year in either hemisphere always come before the summer solstice. The exact date of your earliest sunrise depends on your latitude, but the sequence is always the same: earliest sunrise, solstice, latest sunset.
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At mid-northern latitudes in the Northern Hemisphere, the earliest sunrises of the year happen around mid-June, despite the fact that the summer solstice – the year’s longest day – is still about a week away. And if you live at middle latitudes in the Southern Hemisphere, the earliest sunsets take place around now, even though the winter solstice – the year’s shortest day – isn’t for another week.
For those of you who are privileged enough to be outdoors before one of these early sunrises, you’ll find some of the most beautiful dawn twilights of the year.
The exact date of earliest sunrise varies with latitude. At 40o north latitude – the latitude of, say, Philadelphia in Pennsylvania – the earliest sunrise of the year will happen on June 14. For that same latitude, the latest sunset of the year will fall on or near June 27. This is in spite of the fact that the longest day of the year (in terms of daylight) comes on the June summer solstice.
So it is for other Northern Hemisphere latitudes. The dates of earliest sunrise and latest sunset do not coincide exactly with the solstice. Appreciably south of Philadelphia’s latitude, the earliest sunrise has already come and gone (in late May or early June) and the latest sunset occurs at a later date (sometimes as late as July). In Hawaii, for instance, the earliest sunrise precedes the June solstice by about 2 weeks, and the latest sunset comes about 2 weeks after. Farther north, the earliest sunrise and latest sunset happen closer to the June solstice. Check it out at your latitude, using links on our almanac page.
The earliest sunrises come before the summer solstice because the day is more than 24 hours long at this time of the year. In the Southern Hemisphere, the earliest sunsets of the year come before the winter solstice for the same reason.
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
See full size | Sunrise over Currituck, North Carolina. Credit: GregDiesel Landscape Photography
In June, the day (as measured by successive returns of the midday sun) is nearly 1/4 minute longer than 24 hours. Hence, the midday sun (solar noon) comes later by the clock on the June solstice than it does one week before. Therefore, the sunrise and sunset times also come later by the clock, as the tables below help to explain.
For Philadelphia (40o north latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 5:31 a.m. | 1:01 p.m. | 8:31 p.m. | 14h 59m 23s |
| June 21 | 5:32 a.m. | 1:03 p.m. | 8:33 p.m. | 15h 00m 38s |
For Valdivia, Chile (40o south latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 8:12 a.m. | 12:53 p.m. | 5:34 p.m. | 9h 21m 54s |
| June 21 | 8:14 a.m. | 12:55 p.m. | 5:35 p.m. | 9h 20m 42s |
Source: timeanddate.com
Early sunrise in Sweden via Per Ola Wiberg
Early sunrise by Flickr user Raffee
Bottom line: The earliest sunrises of the year in either hemisphere always come before the summer solstice. The exact date of your earliest sunrise depends on your latitude, but the sequence is always the same: earliest sunrise, solstice, latest sunset.
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
Donate: Your support means the world to us
from EarthSky http://ift.tt/1lM9VQO
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