A weekly feature of Torah Tidbits to help clarify practical and conceptual aspects of the Jewish Calendar, thereby better fulfilling the mitzva of HaChodesh HaZeh Lachem...

This Shabbat, we bench Rosh Chodesh Adar Alef, as follows:

ROSH CHODESH ADAR RISHON Y'H'YEH MACHAR B'YOM RISHON U'V'YOM SHEINI HABA ALEINU V'AL KOL YISRAEL L'TOVA

Shvat always has 30 days in our fixed calendar; hence two days Rosh Chodesh for the month that follows it (i.e. regular Adar or Adar Alef). Adar Alef also has 30 days. (Regular Adar and Adar Sheni each have 29 days.)

The Molad of Adar Alef occurs at 7h 24m 14p on Shabbat morning, which is 7:04am Israel Standard Time. Most shuls will be benching Rosh Chodesh later than that time and therefore that announcement of the Molad should use the past tense.

HAMOLAD HAYA (rather than Y'H'YEH)

With sunrise at 6:26am, even Vatikin minyanim will probably not bench Rosh Chodesh before the Molad. Points east of Israel - Australia, for example - should use the more common Y'H'YEH (will be) when they announce the Molad.

The two Adars can be called Adar Alef and Adar Bet, Adar Rishon and Adar Sheni, or Adar and V'Adar. Strange as it may seem, the third pair of names says it best.

In years with two Adars we can view things as the second Adar is the added month, and then Purim and the 4 Parshiyot get moved into it - rather than looking at the first Adar as the added month. There are differences.

Forget Ya'aleh V'Yavo on Rosh Chodesh in Birkat HaMazon - do not repeat. In Amida of Maariv - don't repeat. In Shacharit or Mincha - repeat.