Since I've had my 95 Cherokee Country, it's always made this slight howling noise that lasted about 3 seconds when you first turn it on. We charged the a/c this last weekend, and now the howling noise has gotten worse, louder, and lasts longer. It doesn't matter if I turn the jeep on with the a/c on or off, it does it on "max, norm, and bi-level", but not on vent. I need to fix it, since it's 104 degrees here!! Any ideas what it could be?? Anybody ever dealth with this before??

 

Could be the compressor starting to fail, but there was a TSB from Chrysler back in 1995 for noisy A/C compressors. The cure was to replace the reed valve block in the compressor. I did a bunch of them in my dealership days back then, now you just replace the compressor.