Outdoor Winter Wedding in Phoenix

I have read a couple posts about winter weddings in Phoenix and wanted to get some insight. We are looking at having our wedding in February at the Desert Botanical Gardens. The one location that is available is the Webster Center which includes a large outdoor space and a small indoor space. Would it be too cold to host the ceremony and main part of of the reception outdoors? Luckily the Webster center has a historic building that we can use. I was thinking we could use this space for cocktail hour and lounge space for guests to hang out indoors/warm up during the reception. We will have lots of heaters as well to keep people warm. Will that be enough to keep people comfortable? Obviously we will ask guests to being jackets to stay warm and provide blankets.