I pre measured 3 batches of yellow cake, but found that I dont need one batch. It is just the dry components, cake flour mixed with baking powder. Will it be ok if I store it? or do I have to use it and make a cake out of it today. I do plan on making the recipe again, just not to soon.
Thanks.

My guess is that it will be fine stored in an airtight container at room temperature. Afterall, isn't that what a cake mix is? ... all the dry components? (Makes sense to me.)

I pre-measure my regular recipes all the time. What really helps is to keep a copy of the missing ingredients with the dry pre-measured. I usually put the dry stuff in a zip lock, and write the rest of the recipe on the bag. That way I don't have to guess what I put in or what still needs to be added.