My great Aunt and Uncle lived a couple of miles from the National Radio Observatory in Greenbank, WV. The entire valley is about 3000 feet up, with the ridges around it about 1500 - 1800 feet higher. They have hard winters due to the elevation.
The observatory requires a radio/tv dark zone of over 200 square miles. About twenty five years ago they started getting random on and off interference during the winter, usually during the coldest days/nights of winter.
It took the Feds over two years to run down the source. An electric blanket in a dog house with a second rate timer. The folks at the observatory shelled out a few bucks, they bought the lady a heavily insulated dogloo for the pup. No more interference.