Thanks for your suggestion.
Yesterday when the car wouldn't start, I turned the windshield wipers on and they seemed to be perhaps just a little bit slower than normal but not slow enough for me to suspect the 12V battery. The car hadn't been driven for about a week and during that week it was significantly colder.
Today, slightly warmer, per your advice, I measured the battery voltage. It was 11.97 Volts.
I started the car and it started normally. On colder days is there a low temperature cutout limit?
When the car is armed by temporarily turning the key to its furthest position, is there a certain amount of current that must be supplied to ensure starting?
The car is a 2012 and the battery has been maintained, but I suspect that a new battery would have prevented this issue.