I'm sorry you didn't find our response helpful, Renee! Let me see if I can clear this up.  Morgan is correct that we have not found freezer storage to affect the weight of flour as long as it is in an airtight container, which I believe answer's Alex's original question of whether flour stored in the freezer would change in weight. Since all of the moisture in the freezer should be frozen solid, it will have a tough time being absorbed by the flour so whatever moisture that is in the flour prior to it being frozen will stay in the flour.

However, if flour is not stored in an airtight container, then moisture could sneak its way into the flour over time creating a more dense flour that could be potentially heavier by the cup. This could happen if it is stored in the freezer, fridge or just room temperature, especially in a humid environment, so we always recommend storing flour in an airtight container. Still, it is true that the moisture in the air can affect hydration of your recipe, especially when airtight storage isn't an option, which we discuss here in our blog post about Summer vs. Winter baking. 

To Morgan's point, volumetric flour measurements can vary quite drastically depending on how the flour is resting in the cup and whether it is compacted or not. While King Arthur considers 113g of flour to be one cup, other recipe writers may consider it to be 150g which all depends on how densely the flour is compacted into that cup. This variation combined with moisture being absorbed into flour stored in a non-airtight container offers explanation to the confounding factors in the discrepancies Alex is noticing at home when evaluating the figures on our Ingredient Weight Chart.  I hope this helps clear up the confusion!

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