What is the neutral/non-negative proper term for the "mousy" hair color?

I don’t mind hearing dishwater/ditchwater blonde. I’m blonde, but only in the spring/summer is it bright yellow. By December it’s back to dishwater- an ashy gray. I was born and raised with white-blonde hair, but of course it darkens over time, hence my dishwater all winter. Soon as real sun hits it, it looks like I’ve had a dye job. Currently its bright yellow again. But then I don’t give a whit about my hair as long as it fits in a ponytail and is out of my face.
Proud dishwater blonde, here, though ash blonde is the preferred term…