First Grow - Cookies Kush

No, it's not normal, but hardly harmful, if anything it's good to have low humidity in flower, less chance of mildew or budrot. Plant transpires almost 100% the water they drink, that means that as they explode with growth during the pre-flower stretch and they drink more and more water, they will release it into the environment making RH rise. That been said, humidity which is actually relative humidity changes a lot with temperature, 60% humidity at a certain temperature can drop drastically if the temperatures increases just a little. Perhaps your weather has changed and the air is drier than a few days / weeks ago?

Hi mate, I've done similar thing before, but theres no harm done in using water through to the finish. No point wasting nutrients now as she is very close and not far off. I'd rather a clean product than a nutrient filled one. At least now when she is ready by trichomes or which ever way you prefer to asses her, she will be ready without having to re flush. You're on track and don't worry. A big flush is better than no flush, plus some growers go from start to finish without any nutrients and still get a nice clean product. Hope this helps.