I wonder if living near the golf course makes a difference. If you have a breeze there due to the open area, there is no area for the cold to air to pool since it will settle in low lying areas. For instance, KSWF is at 581 ft. IMBY, I'm at 125 ft. in Butterhill along the Moodna creek bed shelterd from the wind. I can be a couple of degrees colder than KSWF. It could be just a slight breeze that makes a factor. Just my thoughts. My forcast low is 11 for tonite, currently at 19.1.