I've got a 1998 Cherokee Limited, 4.0

Runs like a top! getting 19.5 mpg average.

Changed the valve cover gasket a month ago and have been periodically checking the oil and noticed it a bit low, so I went to add some oil today and noticed that my coolant resevoir was dry! Oil looks clean and radiator fluid is dirty green with some stop-leak junk in it from PO (getting it flushed this weekend)

It went from 65 degrees to 90 this week (Columbus OH) and has been HOT for about 4-5 days, but I didn't think evaporation would be an answer to this.

I haven't noticed any coolant leaks but have noticed an anti-freeze smell in the jeep from possibly gunked up or bad heater core?

Any thoughts? No white smoke, and I'm not sure how to check for a cracked head gasket, but I do know that if the oil looks weird / dirty then it could be a problem. I searched for this and found a few things but mostly head gasket repairs.....

All these little issues are eating into my fun fund!

What should I look for / do next?

 

start by checking all your hoses then check the water pump see if its weeping from under neith,check your cap on the radiator,put some water in the bottle to make sure there isn't a crack.Also look at the heater control valve.