Found out why I have water dripping: It’s snowing in my attic. The wind is blowing hard enough to push snow through the gable vent, which the bathroom vent and light fixture is directly below. I stapled a contractor grade garbage bag over the vent, so hopefully that will do the job for now. As for the snow, I guess it will just melt/evaporate/sublimate, hopefully before it causes damage or mold takes hold