I was a bit anxious about driving a diesel Saab in Norway where the weather can get really cold. On Christmas Eve e.g. the temperature read -35 degrees Celsius on my car! But I had no reason to worry. The HVAC system in the new 9-5 is without any doubt engineered by Saab to cope with Scandinavian winters. The cabin heats up very fast and snow and ice melts off the windows. Compared to my previous Saab, a 2003 Saab 9-3 1.8t SportSedan, I believe this new 9-5 has an even better HVAC system!
My only gripe with the HVAC system is the buttons. I wish the HVAC buttons were shaped and located in such a way that I can operate them without having to look to ensure that I hit the right button. Bigger buttons and farther apart from eachother please!