Originally Posted by atcguruaf
But it seems odd to say "make left traffic" if they're closer to the base leg. I'd say "enter left base".
It's more a reinforcement because I've seen it happen where a pilot on the right traffic side flew over the airport to go enter a 45 for left traffic because left traffic is standard at the vast majority of airports. We have parallels here(GFK too) and as a local controller you always run your patterns to the outside to keep traffic away from the other parallel.