Cold enough to kill hogs

Have Yall ever heard "Cold enough to kill hogs".

Where did that come from?

I was a farm girl but I didn't pay attention. So I'm a little fuzzy on details. But here is the general idea. Before refrigeration, hogs were killed in cold weather. The meat could be placed in "meat houses," as in "cold as a meat house." Preserved with salt, etc. If a hog was killed in hot weather, the meat would rot.