tomorrow is sunny and high of 9, so not bad. Im sure you have your clothes all figured out for these temps as you have been riding here lately, and to top it off, Sunday looks similiar, a bit of cloud but high of 8.
I have driven the Mtl-Papineauville route many times (in winter though, to go to the Canadian Ski Marathon, the Papineauville High School was where many participants slept Fri and Sat night)--the shoulder isnt super great, so as always, be on the ball.
have a good ride