The celebration of the New Month of Nissan starts at sunset on Shabbat, March 13th
On the calendar:
Purim / פּוּרִים
Purim (Celebration of Jewish deliverance as told by Megilat Esther) for Hebrew Year 5781 begins at sundown on Thursday, 25 February 2021 and ends at nightfall on Friday, 26 February 2021.
Purim (Hebrew: פּוּרִים, Pûrîm "lots", from the word פור pur, also called the Festival of Lots) is a Jewish holiday which commemorates the saving of the Jewish people from Haman in the ancient Persian Empire, a story recorded in the Biblical Book of Esther (Megillat Esther).