A temp gun is just that - it's a little hand help device and when you pull the "trigger" a red laser light shows where your pointing and it reads the surface temperature of the specific location. They don't do ambient temperature, but if the inside of the a hide's floor is reading 90, then the air inside the hide is guaranteed to be warmer than the air outside of the hide.
I get mine on amazon for like $20
https://images-na.ssl-images-amazon....S327_QL65_.jpg