This is what worked for me last year.
Right now, my cut off is freezing.
30 - Performance brand tights thermal over shorts, LS T, LS jersey, PI barrier jacket, winter gloves and liners
35 - Performance brand tights thermal over shorts, LS T, red Gore phantom jacket, winter gloves and liners
37 - Performance brand tights thermal over shorts, two LS T, PI barrier jacket, winter gloves and liners
(noted that I may not have needed both Ts
)
38 - Performance brand tights thermal over shorts, LS T, Novara jacket, winter gloves and liners
(the Novara jacket is lighter and more breathable, I didn't see it on REI's website but it retailed for about $90
)
39-66, wind 5-10 - capris over shorts, LS T, Novara jacket, sleevelss jersey, summer gloves w/ liners, mtb socks
40-50, wind 5-10 - Performance brand tights over shorts, LS T, Novara jacket, winter gloves and liners
I pretty much stick with tights
(no chamois
) over shorts with a LS T and Novara jacket until about 48 degrees. I switch to capris then and shorts at 55 or so.