We begin praising G-d for giving us rain by saying mashiv haru’ach umorid hageshem (He makes the wind blow and the rain fall) in the second blessing of the Amidah on Shmini Atzeret day. Although the rainy season (in Israel) actually begins on the first day of Sukkot, we do not mention rain in our prayers during Sukkot as rain in the Sukkah is a sign of a curse.
We do not begin mentioning rain on the eve of Shmini Atzeret since not as many people come to davening in the evening as do in the morning. Nor do we begin mentioning rain in Shacharit (morning prayers) of Shmini Atzeret as it is forbidden to interrupt between the blessing of Ga’al Yisrael and the Amidah in order to make the announcement of Mashiv HaRu'ach.
Nevertheless, we don't begin asking for rain in our weekday prayers (in the ninth blessing of the Amidah) until the seventh of Cheshvan in Israel or the fourth of December in the Diaspora.
- Prior to Mussaf, the Gabbai announces that we begin saying Mashiv HaRu'ach U'morid Hageshem (G-d makes the wind blow and the rain fall). As mentioned, this is added in the second bracha (blessing) of the Amida. “The Sages placed the mention (of rain) in the blessing that praises G-d for resurrecting the dead because the rains are considered equivalent to the Resurrection. For just as the Resurrection of the Dead (brings) life to the world, so too, rains [bring] life to the world.”
- The Chazzan recites the special Tefilla of Geshem - prayer for rain (Siddur pg. 355) - during his repetition of the Musaf Amida. It is not the Chabad custom for the Chazzan to wear a kittel for this prayer.
If One Forgot
Following the announcement, if one forgot to say Mashiv HaRu'ach U'morid Hageshem, the halacha is as follows:
- If one at least said Morid Hatal (G-d makes the dew fall) [this praise is recited during the summer by Sefardim as well as by Ashkenazim who pray Nusach Sefard or Arizal], he need not repeat the Amidah. Nevertheless, if one realized his omission before saying the name of G-d at the end of the second blessing (mechayeh hameitim), he may insert Mashiv Haru’ach etc. in the middle of the bracha at any point before the words "Baruch Attah..."
- One who didn't say either Mashiv HaRu'ach or Morid Hatal and already completed the blessing and started the next one must stop where he is and repeat the Amidah from the beginning.
- One who only remembered after completing the entire Amidah should repeat the Amidah.
- If one remembered before beginning the next bracha, he may say it at that point.
- One who is praying alone on the morning of Shmini Atzeret should not pray Musaf before the time that the announcement of Mashiv HaRu'ach is made in Shul.
- One who heard the Mashiv HaRu'ach announcement before davening Shacharit (praying the morning service) must say Mashiv HaRu'ach when he prays Shacharit if he is praying without a minyan.
