When will the December full moon occur? Tips for viewing the final supermoon of 2025.

The year 2025 will conclude with its final supermoon, lighting up the skies above Oklahoma City with one of the brightest full moons of the year. A supermoon occurs when the moon is at its closest point to Earth, making it appear slightly larger and more luminous than usual, though the difference is subtle to the naked eye.

This last supermoon is the third in a series of four consecutive supermoons that began in October. On Thursday, December 4, the December full moon will rise just before reaching its full phase. The moon will appear above the horizon at 4:51 p.m. CST and will officially become full at 6:14 p.m.

For those wanting to see the supermoon at its peak, it will reach the highest point in its path across the sky at 12:37 a.m. CST on Friday, December 5. A supermoon is defined as a full moon occurring within 90% of its closest distance to Earth, which slightly increases its apparent brightness and size.

In 2025, there were three supermoons, all appearing in the final months of the year. According to the Old Farmer's Almanac, they were:

• Harvest Moon Monday, October 6 at 10:47 p.m. CT
• Beaver Moon Wednesday, November 5 at 7:19 a.m. CT
• Cold Moon Thursday, December 4 at 5:14 a.m. CT

The sequence of supermoons will continue into 2026, beginning with the January full moon on Saturday, January 3, which will close the four-month run of consecutive supermoons.

The December full moon is traditionally called the Cold Moon, a name used by the Mohawk tribe to mark the arrival of winter. Other Indigenous groups have their own seasonal names, such as the Snow Moon by the Haida and Cherokee, or the Long Night Moon by the Mohican tribe, reflecting either the cold weather or the upcoming winter solstice.

Author's Analysis: December's Cold Moon Supermoon

The final supermoon of 2025 offers a notable astronomical moment for observers in Oklahoma City. While the increase in apparent size and brightness is subtle, the alignment of the moon’s closest approach to Earth with its full phase creates a visually enhanced experience.

This December supermoon completes a series of three consecutive supermoons that began in October, following the Harvest and Beaver moons. Its timing, with the full moon rising at 4:51 p.m. CST and reaching peak altitude at 12:37 a.m. CST, provides ample opportunity for evening and early-night observation.

Beyond its visual appeal, the Cold Moon carries cultural significance. Named by the Mohawk tribe to mark winter’s arrival, it also aligns with similar seasonal names across Indigenous communities, highlighting a longstanding human tradition of linking lunar cycles to environmental changes.

Looking ahead, the supermoon sequence extends into 2026 with the January full moon, signaling the continuation of this rare, consecutive lunar phenomenon and maintaining public interest in observable astronomical events.

Sources:

• When is the December full moon? How to see last supermoon of 2025

Author: Olivia Parker
Olivia Parker is a journalist and editor with over 8 years in media. She focuses on culture, arts, and social issues, skilled in feature writing and critical reviews.