This comic is inspired by XKCD and recent events and observations in my life. Disclaimer: I have no artistic ability and blatantly rip off the XKCD style and artwork, however the idea is mine and I feel it fits.
edit: so it seems that if there is significant day/night temperature difference in your home, that can be a factor and it may not be only about selective memory.
yeah, the current issue has zero science in it, but your comics presents dumb folks' wisdom (untrue and unscientific) and present it to look somewhat "scientifically", which is imho against the general ethos of xkcd.
the alarm doesn't really go off more often at night.
it is just that when it goes off during the day, you fix the problem and move on. when it goes off during night, and presumably wakes you up, it pisses you off and you tend to remember it more due to associated emotions.
It could be that extended lower temperatures at night slow battery chemistry to the point where the voltage sags below the trigger threshold. It would take quite a few hours to cool the battery down from day time ceiling temps, so this would naturally occur in the early hours of the morning just before temperatures rise again.
Thanks, really no need to apologize. I had assumed it was just selective memory myself and hadn't considered the temp/voltage drop possibility, but now we have learned something.