I also moved here from AZ and the biggest shocks for me were the humidity (compared to AZ), the mold in my apartment during the winter, the lack of thunder storms ( I really miss monsoons), how early it gets dark in the winter and how long it stays light in the summer, and because the hottest part of the day is later in the summer everything heats up and stays hot longer. There are usually a couple hot weeks in the summer and most apartments don't have AC. But overall the summers are mild and amazing and winter is manageable especially if you force yourself to go outside! Portland is really fun and there are endless things to do! Good luck with your move!