I've got to say that I didn't find anything over 35-40 degrees at the steepest in this couloir. Kinda bummed cuz I sure wanted to do something steeper. Sorry, folks - Jepson's got the steep stuff!
If I HAD to give a single number, it would be 37 degrees. I know when I hit 40 cuz I am ready to climb on all 4s. HA! Beautiful climb though, loved every huff'n puff step whilst getting snow on. :)