Road trip....and milk/formula storage suggestions needed!

We are going on a little road trip with 2 week old Elliana to drop my mom off at the half way point between our home and hers. (She's been visiting) Anyways, I recently took LO off the breast and I pump regularly and supplement with formula when needed....so I was wondering how to bring all this stuff with us!

I have a cooler bag with ice packs for breast milk....and I was thinking of making up three bottles or so with the dry powder mix....then just bring water bottles with me to mix it when I'm ready to use?? Does that work?? But I have no way of warming anything up???

Tips and suggestions??