First big snow of the Winter. I hear what sounded like an armageddon of building rumbling and noise outside followed by a notification that my alarm had been activated by sentry mode. I go outside, no damage, no broken windows, not snow tracks leading to the car, not even footprints nearby. Checked the sentry (of which there were 100 false alarms), and the only thing I can think of is that the snow plow that game by was so big and loud and raucus that it triggered the alarm. Do alarm false alarms happen like that? This is the first Winter with my M3.