KOKO

Question
We adopted Koko about 2 years ago when he was 1 1/2 years old. He is Akita/Greyhound mix. Problem- he is terrified to be in the house when it is raining or this year, snowing. He has destroyed the bay window in the living room. Chunks of wood gone and splintered. I have given up on mini-blinds after re-placing six sets of them. After a rain event it may take 2-3 days to get him to calm down. When we let him out in the backyard he will not come back in and there is no catching him (Greyhound).We now take him out back on a leash just so we can get him back inside. But then he isn't getting the exercise he needs. We suspect he may have been trapped in a flooded house before we got him. HELP

Answer
This behavior is SO exaggerated and so over the top that I suspect there might be more to it than a conditioned response created by one event (unless, as you suggest, it was a horrific event such as being trapped in a flooded house!)  It's amazing to me that the dog has generalized SNOW to rain and I'm wondering if this is a visual stimulus, rather than auditory, especially given his barrier frustration behavior (eating the window, tearing down blinds, etc.)  This can't be the rain or snow ITSELF, but rather the SOUND or SIGHT of it FROM INSIDE, since he will go outdoors and then not want to come back in.

I suggest you have this dog totally evaluated by a veterinarian who is knowledgeable regarding neurological problems and seizure disorders.  You may very well be seeing a seizure related phenomenon that is triggered by the stimulus of rain (the sound on windows or streaking, something which could trigger seizures much as flashing lights do in humans).  Between then and now, observe the dog to see if anything else (either visual or auditory) might be triggering lower level responses (which you may not have noticed.)  In any event, while medication won't prevent the panic it can certainly reduce the length of time the dog is suffering.  You might ask the veterinarian for phenobarbital, which is also used to treat seizures, and which you can give the dog during a rain storm.

If your dog comes back with a clean bill of health, re-post and we will tackle it behaviorally; but I would like to see the Vet give you some sort of non-stupefying medication you can offer the dog during rain storms.  This won't be an easy fix by any means.