Thank you for the replies!
I haven’t measured precise temperatures, but in the summer I figure the high is something in the 90’s (F). There is plenty of ventilation, so I figure temperatures are fairly similar to outdoor temps. In the winter the interior of the barn probably stays somewhat higher than the outdoor temperature. Water in buckets for the horses does not freeze. The temp may dip below 32F for short periods, but I don’t think we have extended periods below freezing.
The range of temperatures would certainly be much narrower than what the electronics in my car are exposed to. That gets much hotter and much colder than the interior of the barn.
The barn complex is a pretty large building:
Image of barn
The office area is in the front, with the “barn” along the back.