Anyway, I was surprised by the lack of water use last night. It seemed to be about an inch or two, rather than the more-than-half of the previous night and the nearly-all of the night before that. So I thought the weather was warmer, thus the heater hadn't been on much.
Um. No. 23 whole degrees by the bank thermometer this morning.
Perhaps I just waited too long to start the humidifier so the apartment dried out and now my apartment is finally equilibrated to the 45% I have the humidifier set at?