I've got nothing here. No people coming out to look up. No police arriving. Maybe the sound was added later to the video? If not, maybe this is a nightly happening. It's stange than nobody bothered to gawk. People love to rubberneck. I have no idea what it could be. If it's steam being vented, it is one hellaciously loud vent. The building looks deserted, so I doubt anyone's firing cannons from the roof. I doubt it's a training exercise at 3 AM.