For some background info, it's a 2004 sedan with the 2.7 with 152k. Car runs well with tons of new parts, but recently I have been having some annoyance issues that I want to fix before winter hits. First off after a cold start, I get a nice squealing noise that sounds like a belt, but the belt is new and is conditioned, so I thought it was a pulley. I sprayed some wd-40 on the alternator pulley and the noise instantly goes away. The noise also is loud after the car has sat out in the rain, and it does get louder with increases in rpms, but the noise goes away after driving for a bit. Would a replacement alternator solve this? But my main concern is why would it get loud after just sitting in the rain? Moisture in the air? Either way, it is extremely annoying and shows no other issues other than the noise. Any help is appreciated.

The other noise comes from when accessories ie. a/c and heat come on. Is there another pulley that could be the culprit?

 

Here is some information on fan belt adjustments.
ADJUSTMENT - 2.7L ACCESSORY DRIVE BELTS
NOTE: A belt is considered “used” after 15 minutes of run time.

AIR CONDITIONING COMPRESSOR/GENERATOR BELT TENSIONING
WARNING: DO NOT EXERT MORE THAN 190 N·m (140 ft. lbs.) OF FORCE ON AIR CONDITIONING COMPRESSOR/GENERATOR BELT TENSIONER BRACKET DURING TENSIONING PROCEDURE.

NOTE: Ensure lower tensioner bracket bolt is finger tight/seated to prevent bending.

NEW BELT
Engage a torque wrench, with a maximum 2 inch extension in the 1/2 inch square opening of the tensioner bracket (Air Conditioning Compressor/Generator Belt Adjustment - 2.7L).
Apply 141 N·m (104 ft. lbs.) of torque, counter-clockwise to the tensioner bracket while tightening the upper fastener. Torque fastener to 28 N·m (250 in. lbs.) (Air Conditioning Compressor/Generator Belt Adjustment - 2.7L).
Remove torque wrench from tensioner bracket, and torque lower tensioner bracket fastener to 28 N·m (250 in. lbs.).
Verify proper belt tension.
USED BELT
Engage a torque wrench, with a maximum 2 inch extension in the 1/2 inch square opening of the tensioner bracket (Air Conditioning Compressor/Generator Belt Adjustment - 2.7L).
Apply 96 N·m (71 ft. lbs.) of torque, counter-clockwise to the tensioner bracket while tightening the upper fastener. Torque fastener to 28 N·m (250 in. lbs.) (Air Conditioning Compressor/Generator Belt Adjustment - 2.7L).
Remove torque wrench from tensioner bracket, and torque lower tensioner bracket fastener to 28 N·m (250 in. lbs.).
Verify proper belt tension.
POWER STEERING PUMP BELT TENSIONING
Insert a 1/2” drive breaker bar into the square opening on the power steering pump bracket.
Hold clockwise pressure on power steering pump bracket and tighten adjusting bolt.
Verify proper belt tension.