My job is to do weather observations every half an hour, or when the situation changes drastically enough to warrant an update. I used to get a bit stressed out about noticing the clock approach one of the routine times while not at work (because that's when I haven't been keeping an eye on the sky so oh shit now I gotta figure it out fast!), but I think I've gotten mostly out of that pavlovian response. Many of my colleagues say that they also get this. But the phone alarm (a manufacturer default) that goes off at that time as a reminder definitely triggers it. Luckily I've only heard it like once or twice outside of work.