I agree with that logic. Wherever they come from, plants would naturally experience fluctuations in temp, 20-30 degrees difference between day/night. I'm not fan of gray skies either, having the same thing here. At least it's still warm enough to have windows open, though Friday night looks like some heat may be required - 37 already?! Just one night, but that's pretty cold if you're a tropical plant (or wannabe tropical person!)
