Overheating and leaking '93 Grand Am GT

My 1993 Grand Am GT is having some problems right now with overheating. It was doing fine until I moved to bakersfield for school in the fall, but now that the heat has kicked in, the temps rise really quick and it seems like no amount of coolant can keep the temps down. I must mention that I have a coolant leak, but for right now, I just want to drive back to Paso Robles for the summer, and once I get there, I can work on it properly. Is there anything i can do to keep it cool while I drive back? I was reading through some posts and saw that a dirty cat might make the engine heat up. How would I clean this? Is there anything else I might try and do? Thanks for your help in advance.

I have 2 questions for you: Which motor do you have and where are you loosing coolant? make that 3, how many miles on the motor?

I have the 3.3 liter V6, leak is coming from around the overflow tank, and the engine has 142,000 miles on it.

I'd start with the thermostat first, its inexpensive and really easy to change. It might be sticking shut. If that does not work, see if the radiator is flowing, the way i tested mine was i took it out and ran water through it in the bathtub. If that doesn't cure it, I'm out of ideas. my 95 gt ended up having a blown head gasket, and that was discovered when I found antifreeze in the oil.