The final in a trio of year-ending supermoons takes center stage Thursday, reaching its fullest point just in time for an evening show.
Typically called the Cold Moon, our cosmic neighbor will become 100 percent full at 6:14 p.m. Eastern time. This is the third consecutive supermoon to close out 2025 and the third of four in this series. Somewhat more distant than November’s supermoon but nearer than October’s, the moon’s proximity to Earth will help it shine extra bright.
Moonrise occurs at 4:13 p.m. in Washington, D.C., or about 30 minutes before sunset. Similarly, in Los Angeles, a 4:22 p.m. moonrise teams up with a 4:43 p.m. sunset. These are also some of the earliest sunsets of the year as the winter solstice nears.
The moon will sit squarely above the horizon in the east and northeast sky throughout the evening and rise higher into the night. Large portions of the country should get a view.
What’s in the name?
Full supermoons happen when the moon is at or near perigee, the closest to our planet along its elliptical orbit. When a full moon is at apogee, its furthest distance, a full moon is called a micromoon. NASA notes that full supermoons appear as much as 14 percent larger and 30 percent brighter than when there is a micromoon.
The name of December’s Cold Moon is probably not too surprising. With the beginning of meteorological winter at the start of the month and astronomical winter near its end, the cold season is taking hold across North America. The name is particularly apt this year as record cold descends through the Midwest on track toward the East Coast.
December’s moon is also called the Long Night Moon and Oak Moon, according to Royal Museums Greenwich.
The best time to view the moon
Moonrise will be particularly well timed for viewing during the evening. This is when the moon illusion is at its most potent.
As the moon is low on the horizon, it appears magnified to our eyes. The reasons are not completely understood, although the visual cues of natural and human-made structures seemingly enhance the effect.
Additionally, it will be rising during the admittedly short late fall blue hour between sunset and darkness. During this period, lower contrast from the dim light makes for appealing viewing by eye and particularly through the camera lens.
And while the midday sun is nearing its lowest angle above the horizon of the year in the Northern Hemisphere, the moon is doing the opposite. This supermoon will rise higher into the night sky than any other in 2025, providing a bright night light in locations that don’t have to deal with cloud cover.
The sky-cover forecast
Ideal viewing looks possible in several sections of the Lower 48 on Thursday evening.
In the east, the northern Mid-Atlantic and Northeast are primed for clear views. Around D.C., best odds probably come early with clouds increasing at night.
Across the South, Southeast and Florida, clouds may frequently obscure the moon.
The Midwest should have plentiful peeks, as will places back across the central Plains into the Rockies. When you’re outside for viewing, do bundle up in this region with record cold also on tap.
It’s more hit-or-miss in the southern Plains, as clouds drape along a front across the southern Rockies to the Tennessee Valley region. Clouds could also be numerous along the northern Gulf Coast and westward through Texas.
Out west, Southern California, much of Arizona and northward through Nevada should see plenty of clear conditions. It’ll be partly cloudy for central and Northern California, with some fog risk in the Central Valley. Potentially iffy viewing is forecast for the Pacific Northwest, where the most consistent overcast likely resides in Washington state.
Keep looking up
If you miss it tonight, the moon will still be around 99 percent fullon Friday.
Other sky sights this month include a conjunction of the moon and Jupiter next Monday evening, the Geminid meteor shower which peaks Dec. 13-14, and Comet 31/ATLASat its brightest about a week before Christmas.
The next full supermoon will occur on Jan. 3. After that, 2026 ends with two in a row during November and December, including one on Christmas Eve.
The post Look up tonight to see the year’s final supermoon appeared first on Washington Post.
