Weather....when do you just don't bother?

I haven't found the upper limit yet. I saw high 120's (126, 127?) this summer. I of course really scaled back the efforts and stayed on top of hydration, but didn't feel like I was limited by it. On the cold end, I showed up to a Skypark XC race in regular gear (except I forgot my gloves!) in 29* (race start aat 32). I don't know what the coldest weather I rode in when I was in Alaska, but I don't think substantially colder.

Bare in mind, back in my active duty days, I would see 200* inside the engineroom where I was working. At that point, you were limited to 8 minutes at a time in the engineroom, according to the rules (rarely enforced). Of course, that was near 100% humidity too, as we are on the ocean with sea water temps in the 90's. I was also on the helo refueling team, so I would be on the flight deck during flight ops, and the helo didn't stop flying because of snow!

The truly important thing is find your limits and staying in them. If that is 80*, so be it. Riding is supposed to be fun, if you aren't enjoying it, then you are doing it wrong!