It's gospel among serious bakers that measuring by weight is far more accurate than measuring by volume. However, I'm not sure that measuring by weight helps at all when you have varying humidity levels. It seems to me that, if the recipe author has much higher or lower level of humidity in their kitchen than you do, measuring by weight would tend to make differences in water balance even worse.
For example, I recently made the same pizza dough recipe in my apartment (65F, 80% humidity) and at my in-laws (75F, 35% humidity). Getting the same texture of dough was a difference of 2/3 of a cup of water, or around 6oz of weight. This water already was clearly in the flour in my apartment, adding to its weight but adding somewhat less to its volume. This means that if a recipe was written by someone in Tuscon and I made it in San Francisco, I'd get a sticky mess of a dough without enough flour.
Unfortunately, I'm not in a position to make repeated experiments in measurement at different humidity levels to see if weight or volume is more accurate when the hydrometer is going up and down. Is anyone?
Best Answer
Changes in the weight of ingredients due to humidity are very small compared to changes due to how loose or tight your flour gets packed into the measuring cup.
Weighing the ingredients eliminates one (major) source of measurement error. You'll still have to compensate for other things on your own.