It can be heartbreaking to watch: Even before the first clap of thunder, otherwise well-behaved dogs begin to pace, pant, cling to their owners, hide in the closet, or jam themselves behind the toilet. In severe cases, they’ll claw through drywall, chew carpets, or break through windows in their escalating panic.

Thunderstorm phobia in dogs is real, not uncommon, and shouldn’t be ignored, experts say.