Hi, Having worked in Mesa, Pheonix, Arizona I know the vast difference in location, from downtown to the suburbs to old towns
In Mesa it would not matter where you put your loft the pigeons would bake anyway where as in Snowflake and Pinetop you would batten down you loft for the winter
Position your loft where the birds are going to get plenty of light, make sure your vents are not towards the prevailing winds to stop the damp weather being blown in, I assume yours comes from the south west and the cold from the north west?
Are you in the north beside the lakes or the south. I take it from the swamp in your garden it is quite damp in your area