AC problem with my Jeep...?

you may have a small leak stores sell kites where you can use a light that will show you where and if there is a leak if its very hot out sometimes it takes a car some time to cool down you might even be low on coolant when the engines cooling systems are not at there best or level is low that will mess with the cooling of the cabin area of the car i would recommend looking at your coolant also check to make sure your engine fan is coming on when the car gets to the operating temp that it should be at check to see if there is something blocking the radiator like a bag or some kind of blockage. also make sure you use the correct type of refrigerant for that jeep because that can cost more money then anyone would want to pay it can cause damage to the ac and make it run a little warm or not run at all that's one big thing you must check the type that it takes

You might need more freon.

The best thing to do would've been to buy a can of freon that comes with the guage and it'll give you a better idea of how much is in the system.

You should never have to add freon. If you do, you have a leak. Over maybe 10-12 yrs freon will find its way out, but maybe a few onces at worst. Having a guage is the only way to determine if you need more or not.