Q. Two questions on Shavuot. When do you light candles the first night of Shavuot?

A. Mishna Berura (494: 1) writes that we wait to recite Maariv until nightfall so the forty-nine days of the Sefirah are completed. Although Shloh (beginning of Shavuos tractate,) Mogen Avrohom (ibid.) and others maintain that we are only concerned with making kidush and eating before nightfall and not with reciting Maariv many do wait.

As far as women lighting candles before or after nightfall, there are different traditions. Lehoros Nossan (7: 31) explains that even though women are exempt from the time linked positive commandment of Sefiras Haomer, waiting until nightfall in Shavuos is not a direct result of complying with this mitzvah. Rather it relates to the fact that the date of Shavuos is not mentioned in the Torah but depends on the omer counting, therefore to follow that dictum, we should light candles after completing the count.

Horav Shlomo Miller’s Shlit’a opinion is that one should follow his family tradition. When that is not known, he suggests to light early as with all other Yomim Tovim. (He quoted Shulachan Oruch Horav that mentions to have in mind receiving only Tosafos Yom Tov and not the kedusha of Yom Tov Itself)

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a