AC blows cold on the motorway but warm in traffic, what's the cause?

[jordanwood]

My Wrangler's AC has been doing this thing for a couple of weeks where it's genuinely cold once I'm moving but the moment I stop at a signal it goes warm and humid, then picks up again as soon as I pull away. It's not dead, it's just useless exactly when I need it most, which in MBZ City traffic is basically all the time. A neighbour mentioned there's a helpful explanation of Jeep AC problems at idle near MBZ City that covered his own issue, though he never told me what his turned out to be. I'd rather hear from people who've dealt with this directly. Was it the condenser fan, low refrigerant, or something else entirely? And did it get worse if you left it, because right now it's annoying but bearable and I'm tempted to just wait until the weather breaks.