You mentioned the RV, so I'll assume that these panels are going to be mounted flat on the roof? In that case, I'd de-rate their output to just 60% of nameplate, especially since you are in a more Northern area. In the real-world, what that means is that what goes into the battery is likely never to exceed [ (160W X 3panels)/12.5Vcharging ] X 60% = 23A. So, your 480W of panels is likely to be no more than 290-300W in the real-world
What you might want to do instead is buy a fourth panel, and wire them 2S2P instead of 3S1P. You can't wire four in series if you buy a cheaper controller that only supports 100V. A somewhat more expensive 150V controller will.
Another alternative is build some kind of mount on the roof of the RV so that the panels can be better angled towards the sun. Of course though, that means the mount has to be movable if you want to park the RV wherever you please.
By the way, I did my Master's at UofI, and lived in the Moscow/Pullman area for more than a decade.
