In many Northern Hemisphere locations the earliest sunset happens a week or two before the winter solstice, and the latest sunrise comes a bit after. The solstice is still the shortest day overall, but clock time, Earth’s tilt, and the slightly uneven speed of our orbit shift sunrise and sunset around it [1][2][3].
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This is one of my favorite “wait a second” calendar facts. Many people assume that the earliest sunset of the year should fall on the winter solstice, which is usually around December 21. In reality, at a latitude around 40 degrees north, the earliest sunset tends to happen around December 8, and the latest sunrise happens in early January. The U.S. Naval Observatory gives that as a typical pattern for places like Denver or New York [1].
The key idea is that the length of the day and the clock time of sunrise and sunset are not identical problems. The solstice is the day when the Sun reaches its lowest noon height and we get the shortest span between sunrise and sunset. But the times shown on our clocks are based on an average Sun that runs at a steady pace, while the real Sun speeds up and slows down a little during the year because Earth’s orbit is slightly elliptical and the axis is tilted. This difference is called the equation of time [2][3].Around December, the real Sun crosses the local meridian a few minutes later each day compared to the average Sun that our clocks assume. That shift nudges sunset later even while the total day length is still shrinking. The result is that sunset starts to “turn the corner” and move later before the solstice arrives, while sunrise keeps moving later into early January [2][3].
In Short
- Look up a sunrise and sunset table for your city and check the dates of the earliest sunset and the solstice. The pattern jumps out once you see the numbers side by side [1][2].
- If you enjoy graphs, plot sunrise and sunset times for a few months around December. You will see sunset hit a minimum and then climb while sunrise keeps drifting later.
Bottom Line
The winter solstice is still the day with the least daylight, but it is not the day with the earliest sunset or the latest sunrise. The combination of Earth’s tilt, our slightly oval orbit, and the way we define clock time shifts those events a little to either side of the solstice [1][2][3].
