The Tefilos, They Are A'Changing

"And accept it that soon
You'll be drenched to the bone....
For the times they are a-changin'"
- Bob Dylan, who must have had this post's topic in mind!

Q: What did the yekke tell his wife on the evening of December 4th?

A: Don't forget I'll be home from shul three seconds later tonight; we start saying tal u'matar in maariv.

Yes, tonight we who live outside of Israel once again have that rather oddly-timed change in our davening, we begin inserting the supplication for rain, "v'sain tal u'matar", in the ninth blessing of the weekday amidah. The reasons for this timing are complex, partially given in the 3rd paragraph of the torah.org link above.

Tal umatar is unique among the seasonal tefila variations, in that it's the only one whose onset isn't connected with a Jewish holiday. All other such alterations are either recited exclusively on the holidays themselves - e.g., yaaleh v'yavo, al hanissim - or at least start and end on holidays - e.g., mashiv haruach and the high holiday insertions. And what makes tal umatar even more unusual/confusing is that the drivers for its specific start date depend on the interaction of three different calendars: lunar/Jewish, solar/Julian, and solar/Gregorian (our current secular calendar). Without going into all the gory details (just most of them :-)), here's a summary:

1) As per the link, outside of Israel tal umatar should begin two months after the start of the fall season; i.e., two months after the vernal equinox, or November 21.

2) However, the calculation that is used for determining this halachik date is based on the Julian solar calendar. Therefore, since tal umatar was instituted, its start date outside Israel has slipped a day later, relative to our secular calendar, three times every 400 years, in the years when the Julian calendar has a leap year but ours doesn't; i.e, in 1900, 1800, 1700, 1500, etc. Over time, this slip has amounted to 14 days, so the start date for tal umatar since 1900 has been December 5th.

3) But of course, since Jewish days start the night before, maariv tonight, December 4th, is when tal umatar is actually first said, since this is the first tefila of the Jewish day which corresponds to December 5th.

4) There's a similar interaction of the secular/Jewish calendars in the rule that the start of tal umatar is delayed until December 6th - i.e., maariv of December 5th - in the year before a secular leap year. Here's a succinct explanation provided by Rabbi Elazar Teitz several years back:

"For the purpose of Tal Umatar, halachah considers the year to be exactly 365.25 days long... Each year, the equinox is six hours later in the day than the previous year, because the year's length is a quarter-day more than a whole number of days. Having accumulated three quarter-days, the time of the equinox is after more than half the day has passed, and thus the start of Tal Umatar is delayed one day, to December 5th's ma'ariv."

In any case, whether my little exposition in halachik chronology has enlightened your eyes or just made them glaze over, consider this your official blog-klop: Don't forget tal umatar tonight!