Feast of the Moon seems the closest.
Summary excerpted from the Wiki article on this feast day:
The Feast of the Moon, was an annual festival occurring between the final night of Uktar and the first day of Nightal -- traditionally marking the onset of winter. It was also a time to celebrate and honor the ancestors and the respected dead. Folk blessed their ancestors' graves and performed the Ritual of Remembrance. People also gathered to tell stories of the deeds of their ancestors and of the gods until deep into the night, until they merged and become legend. This was a time to hear of past heroes,
great treasures, and lost cities.
In Faerûn, battles were typically fought between harvest-time and the coming of winter. This meant that most of the fighting usually occurred in the month of Uktar. The timing of the Feast of the Moon—after recently slain soldiers had joined the ranks of the dead—was thus practical, if sadly ironic.