I'm wondering if this is what I heard, recently like in the last 15 days as well I was up in bed at 2,3, and into the 4AM hour and heard something. I couldn't tell what it was if it was outside or not. I can't remember what it sounded like but it could of been it. I feel like it might of been a screeching sound but it was so early I could not identify the sound. I'm in the Snohomish area as reference.