The Fast of Esther (Ta'anit Ester, Hebrew: תַּעֲנִית אֶסְתֵּר) is a Jewish fast from dawn until dusk on Purim eve, commemorating the three-day fast observed by the Jewish people in the story of Purim. If the date of the Fast of Esther falls on Shabbat (Saturday), the fast is instead observed on the preceding Thursday. Like other minor fasts, Ta'anit Esther begins at dawn (first light) and ends at nightfall (full dark).
Ta'anit Esther begins at dawn on Wed, 20 March 2019.
2019 is a leap year when an extra months is added. It's called Adar II and it's the 13th month!