Note that Env. Can. forecast for Thursday's high temp is now -5C. You'll remember that yesterday morning their forecast high for Thursday was +5C. A ten degree difference in 24hrs. Yes that is how bad the Canadian Model is.
Petewawa has dropped 4 degrees in the last 3hrs. So Ottawa will start dropping soon too.
Snow totals for Thursday and Friday still look okay but they may trend toward the low end of my estimate as the NAM model is not showing as much precip as before.
Addendum: Look for low temps in the -20s over the weekend