It was 18°F when we got up this morning. In Texas. And as it didn't occur to us to check the weather conditions before we went to bed, we didn't set taps to dripping and ... the cold water on my sink in the master bath does not work now. The cold water on Toby's sink in the same bathroom still works, as do the shower and tub, so we're a bit perplexed as to what, exactly, may have broken, but we're going on the assumption that 18°F weather and a frozen pipe possibly breaking is the culprit. The sink was fine at 5AM, as I washed my hands then.
At least we can call our own plumber and not whatever low bidder used by a management company. That's what finally spurred us to buy a house: the owner and the management company of the rental we were in weren't willing to invest the money to do proper repairs, so things would just break again.