Overview
December 13 is the 347th day of the year in common years and the 348th in leap years. In both cases there are eighteen days left until the end of the calendar year. The date falls late in the Northern Hemisphere autumn and well into the Southern Hemisphere spring, and it is fixed in modern civil calendars based on the Gregorian calendar.
Cultural observances
One of the best-known traditions tied to this date is Saint Lucy's Day (Lucia), celebrated especially in parts of Scandinavia and in Italy. The feast highlights light in the dark season and is commonly marked by processions in which a woman dressed as Lucia wears a crown of candles. Associated customs include baking saffron-flavored buns called lussekatter and singing of traditional songs.
Historical and seasonal notes
Historically, Dec. 13 was once closer to the winter solstice before calendar reforms shifted the liturgical calendar; this explains older associations between the feast day and the year's shortest day. The date has also been the occasion of a variety of historical events. For example, in 1937 the fall of Nanjing occurred on December 13, an event that precipitated the widespread atrocities later described as the Nanjing Massacre.
How the date is used and recorded
As a day near the end of the year, December 13 is often used as a marker for seasonal business deadlines, end-of-year observances and personal anniversaries. In almanacs and databases it is indexed by its ordinal position within the year and flagged for whether it falls in a leap year — see notes on leap years.
Common facts and distinctions
- Ordinal position: 347th day (common year), 348th (leap year).
- Days remaining: 18 until year-end in both common and leap years.
- Notable cultural observance: Saint Lucy's Day (Lucia), widely observed in Sweden, Norway and parts of Italy.
- Seasonal context: winter approaches in the Northern Hemisphere; associated with light-themed rituals.
Like any calendar date, December 13 gathers a mix of religious feasts, cultural customs and historical anniversaries. Its meaning varies by country and community, from bright processions in dark winters to commemorations of significant past events.