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While I find this hard to believe, I certainly haven’t tested this (from Steve Perry) out myself:

Lens Hoods Cause Blur in Cold Conditions

Joe

Certainly possible if the lens is warm enough - one solution is keep the lens in the trunk so it doesn't heat up, I would think you'd risk fogging bringing a lens into a heated cabin any way.

You can get this problem in unexpected areas. I was shooting across the Pappallacta river in Ecuador in the highlands near Quito it flows down from quite high altitude so is very cold, the river was fast flowing and about 10m across. Distortion of the images was quite noticeable and quite hard to get a sharp image. Cause was cold air currents from the river water mixing with the local air which was significantly warmer.

Wow, this is really interesting!

Any time you have a big discrepancy in temperature of gear and environment it can happen. For astrophotography, I have my scope outside for at least an hour to make sure it's the same temperature before I take images. If you magnify the live view on the camera and focus on something far away, you can see the focus changing due to shimmer.