How many days until the next Long Night Moon?
The Long Night Moon is a traditional name for the full moon that occurs in December, close to the winter solstice in the Northern Hemisphere. It is also commonly called the Cold Moon or the Moon Before Yule. Because the full moon follows the lunar cycle rather than the civil calendar, its date changes each year.
For the 2025 cycle, the December full moon occurs on December 4. The next one is expected on December 24, 2026. That means the exact countdown depends on the date and time zone from which you are checking, as well as whether you count the current day.
A calendar reference such as HowManyDaysIn.com can help separate the lunar event from ordinary date arithmetic. Once the target date is known, the remaining time can be calculated in calendar days, hours, or working days.
What the Long Night Moon means
The name reflects December’s long winter nights. In the Northern Hemisphere, the full moon appears near the shortest days of the year, when darkness lasts longer than at any other point in the seasonal cycle. The phrase is especially associated with the full moon nearest the winter solstice.
Names for full moons come from a mixture of Indigenous, European, and agricultural traditions. They are useful descriptive labels, but they are not official astronomical names. Different calendars and almanacs may use “Long Night Moon,” “Cold Moon,” or another regional name for the same December full moon.
The Southern Hemisphere experiences the seasons in reverse. There, a December full moon occurs near the summer solstice, so the seasonal meaning of “long night” does not apply in the same way.
The next dates to mark
The 2025 Long Night Moon reaches full phase on December 4, 2025, in Universal Time. Local calendar dates can differ if the peak occurs near midnight. The Moon may look full on the evening before or after the official peak because the change in illumination is gradual.
The next December full moon occurs on December 24, 2026. It will be close to Christmas and the winter holiday period in many Northern Hemisphere locations, although the visible timing will vary by longitude and local time zone.
| Lunar cycle | Expected full moon date in UTC | Typical seasonal label |
|---|---|---|
| 2025 | December 4, 2025 | Long Night Moon or Cold Moon |
| 2026 | December 24, 2026 | Long Night Moon or Cold Moon |
| 2027 | December 24, 2027 | Long Night Moon or Cold Moon |
These dates identify the astronomical full-moon event, not necessarily the best local viewing night. Clouds, moonrise time, daylight, and light pollution can matter more for observation than the exact moment of fullness.
How to calculate the countdown
To find how many days remain, subtract today’s date from the next target date. If the result is zero, the full moon is occurring today. If the result is negative, use the following December full moon instead.
A simple date calculation usually counts the number of midnight-to-midnight intervals between two dates. For example, a countdown from December 5, 2025, to December 24, 2026, produces a different result from a countdown that includes both the starting and ending dates. Decide whether the target day should be included before comparing results.
Time zones add another detail. A full moon listed as December 24 in UTC might occur on December 23 or December 25 in a local zone near the date boundary. For an accurate countdown, use the observer’s location and compare the local date and time of the full phase.
Calendar days and working days
A countdown to a celestial event normally uses calendar days because weekends and public holidays still pass while the Moon moves through its cycle. A business-day calculation is useful only when the countdown is connected to a practical deadline, such as preparing a school event, photography session, or winter festival.
For broader planning, it helps to distinguish a calendar month from a fixed number of days. A bimonthly period can mean two months or every other month, and those interpretations do not always cover the same number of days; the explanation of bimonthly periods shows why precise wording matters.
December has 31 days, but the interval to the next December full moon spans part of one year and part of another. Leap years can also affect a long countdown. The year 2026 is not a leap year, while 2028 is, so date arithmetic should rely on actual calendar dates rather than an assumed 365-day cycle.
Why the date shifts each year
The Moon’s synodic cycle, measured from one full moon to the next, lasts about 29.5 days. Twelve lunar cycles total roughly 354 days, which is about 11 days shorter than a solar year. As a result, the date of a named full moon moves through the civil calendar from year to year.
The December full moon can therefore occur early in December one year and near the end of the month the next. It may also fall on different dates in different time zones. The label remains connected to the seasonal period, even though the numbered date changes.
The winter solstice provides another reference point. The Long Night Moon is not always exactly on the solstice, and it is not defined by a fixed number of days before or after it. It is best understood as the December full moon associated with the long winter nights.
Planning a viewing night
The Moon is easiest to notice when it rises shortly after sunset or sets near sunrise, but the ideal time depends on the local moonrise and moonset schedule. A full moon is above the horizon for much of the night, making it a convenient target for casual observation.
Choose a location with a clear eastern or western horizon, depending on the time you plan to watch. Urban observers may still see the Moon easily, although nearby lamps can reduce contrast and make surrounding stars harder to identify.
A countdown can also help organize photography or public events. Mark the target date in a calendar, then check the local forecast and moonrise time closer to the event. The visible disk will appear nearly full for several nights around the official full phase.
Practical ways to track the date
- Record the target date in local time as well as UTC.
- Use a date calculator for the exact number of calendar days remaining.
- Check moonrise, moonset, and weather for the viewing location.
- Treat “Long Night Moon” as a traditional label rather than a fixed astronomical term.
- Recalculate after midnight or when traveling across time zones.
The next Long Night Moon after the 2025 event is the December 24, 2026 full moon. Enter the current date and your location into a reliable calendar or countdown tool to see the live number of days remaining, then use local moonrise information to choose the best night for watching it.