I walked the CF September 10 - October 20, 2022. Although weather can (and does) vary from year to year, last year was unbelievably hot at the outset (first few days were well above 30; one reaching 40). The day I spent in SJPdP on September 9th prior to my departure was cool and damp. A few sprinkles over the first few weeks, but don't think I wore rainwear of any sort before October (Galicia). Burgos was (and I understand often IS) cold. Beyond that, I often needed a warmer jacket (layers), especially when I was starting pre-dawn (probably from around the 3rd or 4th week in September, and thereafter). Had a few days with a fair amount of rain in October, nearing Santiago, but probably only about 3 days of serious rain the whole time. Other episodes of rain were pretty brief. Wishing you favourable weather on your Camino.