Well short post because I didn't get home until very late. But after dinner and putting the kids down (with lots of hugs to make up for lost garden time), I snuck out into the garden. I needed to water so I did that with a flashlight. /sigh
But then I took Ribbit and Toasty's advice. I swapped out the two themometers. Not only is 1 now where 2 was, but the outside is no longer next to the heated family room. Instead, it's under the eve right next to the corn bed. I didn't want to leave it out where it would get rained on, but that spot next to the corn bed gets no rain whatsoever, so it should be good. I also placed it on top of a 2x6 rather than on the gravel to make sure it wasn't registering radient heat from the ground or the house (the garage isn't heated).
Now I know it hasn't been long, only an hour or two, but as of 10:30 pm, the inside temperature is 42.5 and the outside is 39.9 and dropping. All is right with the world again!
Thanks for all the suggestions and late night ponderings. I'm going to take more temperatures and this weekend or maybe sooner I'm going to do a test by placing them side by side to make sure they're both registering the same. This fix almost makes me think they won't. Shame, I want accurate results.
Enjoy your garden, I am mine!