It sounds like you've got a tower system. Given what you've told us so far, I'll bet your fridge is keeping the beer around 40 degrees, but the tap lines can probably reach 50-60 degrees easily. As a result, the beer that sits in those lines (and the pours that go through them) go through a warm line that causes the CO2 to break out of solution. You get a pour full of foam and a mostly-flat beer.
For a system like this, being outdoors, Zamial's suggestion of running your beer line through copper tubing is a possible step. I'd add to that that you should probably build a linkage between the top of the kegerator and the bar, and heavily insulate the tower, and create some way to push air from inside the kegerator up into the tower and back down.
Given your system, though, it might not be enough. Running glycol from inside the fridge through tubing all the way up to the top of the tower and back down might be your only option. That is one way you can probably guarantee that you'll keep those lines cool.
I think your issue will prove to be warm lines. That's an issue that going to longer lines won't help, and lowering your serving pressure won't help. The only solution is to find a way to keep the lines cool.
As for the temp in the kegerator, 36 to 44 degrees is normal if you're measuring air temp. Is it keeping your beer at the right temp? Is the compressor cycling like crazy? Those are the concerns you have for the kegerator. My guess is that none of that is a major issue, although keeping the kegerator outside might kill the compressor (because it will cycle more) earlier than if you kept it inside.