Daylight Saving Time ends at 2 AM this Sunday, at which point most of the country will set their clocks back one hour for no real reason other than that our parents did it. We love us some ridiculous traditions.
It's worth noting ahead of time—since some people genuinely do not know this, but we're not judging—that the sun isn't actually setting any earlier. There is no planetary shift occurring this Sunday. The earlier sunset is in relation to our own 24-hour cycle; most of us haven't mastered warping space-time, yet.
Daylight Saving Time (note the lack of a second "s" in "saving") is a wonderfully ridiculous practice in much of Western civilization in which we set our clocks forward one hour during the warmer months and set them back one hour during the winter. Depending on which version of the story you've read from someone who read it on Wikipedia, there are two reasons behind this twice-yearly shift.
The first is that bumping the clocks forward an hour during the spring and summer months allows farmers to work on their farms later during the growing and harvest seasons. The second version of the story, adjusted for the Modern Working Guy, says that the extra hour of daylight during the spring and summer allows people on an eight-hour office schedule to spend an extra hour outdoors when they get home.
That's mostly true! Assuming that "outdoors" is extended to mean "playing a computer game that takes place outdoors." Let me tell you, that extra hour of sun glare on my monitor really harshes my Flight Simulator mojo. But anyway...
Aside from the havoc it wreaks on us forgetful folk ("oh, there I go writing 'EDT' on my checks again"), the most noticeable effect of setting the clocks back an hour is how early the sun will set. In Greensboro, North Carolina, for instance, the sun rises at 7:42 AM and sets at 6:23 PM on Saturday. On Sunday, the sunrise shifts to 6:43 AM* and the sunset arrives at 5:22 PM. The sunset just gets earlier the farther north you go. New York City's sunset is at 4:51 PM on Sunday, and it'll keep getting earlier until it reaches its earliest setting time of 4:28 PM from December 7 through December 9.
True early-aughts kids will remember that we used to play this ridiculous game a few weeks later and earlier in the year, respectively, but the Energy Policy Act of 2005 extended the period during which we experience a later sunset in order to save energy. It didn't save energy.
Falling back does have one benefit: the weather models come out an hour earlier as they run on UTC instead of mere mortal time. Beginning on Sunday, the GFS starts to drop at 10:22 and 4:22 AM/PM, the first NAM runs pump out at 9:00 and 3:00 AM/PM, and the first graphics from the ECMWF should start to appear around 12:45 AM/PM. Excellent.