Coldest:
1977. I was living in South Lake Tahoe and my gf and I were on our way to Squaw Valley in her car to see Pablo Cruise in concert. With the wind chill, it was 40 below. We stopped just below Tahoe City to watch boats filling up with water from the waves and sinking. When we got back my car was so frozen you could hear the seats crack when you sat in them. On the way home my car overheated because the coolant had frozen.
Hottest:
1984 in Fort Hood, Texas. It was about 100 degrees with about the same humidity. I got heat stroke walking to the PX to cash my check. Being a guy I couldn't ask for help. I cashed my check, bought some beer and took a cab back to the barracks. I then drank and dehydrated myself even further. It's amazing what we can do to our bodies when we are young.
In 1988 at my brothers wedding, it was 113 degrees (Sacramento) and we were in suits. It was stifling.