Reb Eliezer
“October 6 + 60 = Dec 5”
the first day is counted (it (almost?) always is in halacha, eg Milah is on 8th day birth is day 1, bris is 7 days later)
October 7 is day 1
There are 24 days left in October (31 -7) Oct 31 is day 25
November has 30 days nov 30 is day 55
Dec 5th is Day 60 so at the start if Dec 5th (ie maariv the previous day) we say Vesein tal umatar
“Equinox Tekufas Tishri = Sept 23”
i’m not sure where you got that.
Beis yosef OC 117
וכתב הר”ד אבודרהם ויום ס’ יבוא בכ”ב מנובי”מברי (ד’ דעצעמ’) אם היה אותו פיברי”ר מכ”ח יום אבל אם היה פיברי”ר מכ”ט יום תהיה השאלה בכ”ג נובי”מברי (ה’ דעצעמ’) כי תקופת תשרי לעולם שבעה ימים קודם (ד’ או ה’ אקט”ברי)
Tekufas Tishrei occured on September 24 pre advent of Julian Calendar 60 days before Nov 22 (including the first day)
This corresponds to Oct 7 on the Georgian calendar (add 13 days as you correctly pointed out )
The dates added in in the tur were in the 1800’s when Nov 22 julian = Dec 4 gregorian.
since 1900 when the Gregorian calendar skipped another leap year nov 22 Julian = Dec 5th Gregorian
Also note and this is what further confuses people. The Beis yosef is telling you the 60th day of the Tekufa in his day Nov 22 or 23 . but this means that Vesein Tal umatar was said the night prior ie Nov 21 or 22
Its as if you tell your friend PEsach this year is Thursday April 7. This usually means that the Seder will be Wed night April 6. this can be confusing if you’re not clear.