Well it is true, you will never get the result you want in a baked recipe when there is moisture in the air.
I was preparing my weekly batch of Spelt Blueberry Banana muffins, same ingredients each week in their proper amounts but the outcome... not the same. They just didn't want to rise. They normally have this nice little peak in the very center, but not this time. I must mention however, that the slight moisture in the air, brought about a very moist and tender muffin. So the taste, was delicious---they were just a little flatter and smaller than my usual batch. So really you can't beat the heat, when an order comes in, its got to be done. Just be aware that your muffins may not "muff" up like they usually do when the air is wet.