Saturday's sunset was earliest of the year; shortest day comes Dec. 21
Posted December 5, 2020 6:57 p.m. EST
Updated December 6, 2020 10:06 a.m. EST
If you've not complained to friends and family that the Sun sets too early, Saturday was your last chance until next year. Across North Carolina, sunset was at its earliest of the year on Saturday, Dec. 5.
The map above illustrates how widely sunset varies across North Carolina. It was created calculating the latest sunset at 100th of a degree increments or 177,597 points using data from NASA/JPL and the US Naval Observatory. Nags Head saw their earliest sunset at 4:48:10 p.m., and then nearly a half hour later, the sun set on Murphy at 5:24 p.m.
Since late June, sunset has moved earlier and earlier, but those days are behind us. The Sun set on Raleigh a bit (39 seconds) after 5 p.m. on Saturday, the earliest of the year. It will set 2 seconds later Sunday night. The increase in day length is slow at first, with only a few seconds of added sunlight each day.
This picks up pace in January. By June 28, the Sun will be setting more than 3.5 hours later. While the earliest sunset occurs on December 5, it isn't the shortest day. We will continue to lose another 6.6 minutes of daylight until the Solstice on December 21 when the Sun will be above the horizon for just under 9 hours 45 minutes.
By the summer solstice on June 21, we'll have 14 hours 34 minutes of daylight.
Here's why the latest sunset of the year happens a week after the longest day.
These times and other calculations are predictions based on average conditions.
The actual time the Sun is first visible in the morning and last seen in the evening depends on temperature and air pressure at the time. These affect how sunlight is refracted through the atmosphere. The Sun is actually still 0.8333 degrees physically below the horizon at sunrise. That refraction moves the time we first see the Sun by a few minutes each day.