3 ms·

assuming the volume of flour changes with humidity because it contains more moisture, wouldn't it also increase the weight? Not an expert by any means though,

• runxel 6y ago
  No, not at all. Volume ≠ Weight. Another example: Some books use paper with bigger volume (so it looks thicker) but of course they are not twice as heavy suddenly.
• chongli 6y ago
  When flour gets wet, it sticks together to form dough. Dough can have large air pockets in it. Dry flour with a bit of humidity can also form these air pockets, albeit typically on a much smaller scale. Whether you pack flour down or sift it through a sieve into your measuring cup can make a huge difference in the weight.