Belts squeal every time I start my car. It's worse when there's moisture in the air. The car 2003 Sonata doesnt have an on/off switch for the air. I can turn it down but its always on. I've had the belts replaced and adjusted several times at auto repair chains and the dealer. The noise remains. In fact each time its replaced its stops then comes back louder than ever

could be number of things but most usually is the engine drive belts for alternator etc , next time when start engine have some there to spray some WD 40 onto the belts to see if that stops the squeal, if so you will need to check the condition of the belt/s as may need renewing , keep me posted as how you get on

if you can make is squeal parked its easy to find,
can you, or do so at and ASE certified shop,
the belts can squeal, ever check the tension or there conditions?
try belt dressing, it might work for short time (1week) and tell you it is the belts,
its sold in all stores, auto.

find the pulley with the failing bearings and you may get more power when you fix it. The belt squeal is low tension or wrong belt section The belt should be just above the pulley flange and if it is not then it will be running on the bottom of the pulley and that is why it is squealing.

Possible water pump issues

I believe I know the noise that is troubling you. If a new belt is correctly tensioned and still makes such a noise it would indicate either contamination with oil or similar or pulleys that are less than perfectly aligned

The noise and your description is symptomatic of slippage and the pulley that is most likely to be slipping is the small alternator pulley. After starting and when accessories are being used that require a significant current the alternator needs considerable power to drive it in order to produce that current/replace the battery power used to start the engine.

The increased power to drive the alternator must be delivered via the drive belt. As the battery voltage rises the charge rate will fall and the power needed to drive the alternator falls and so the squealing reduces and then stops.

One further thing to note is an engine and it's ancillaries expand or grow quite a lot in engineering terms as it warms up, this has a tendency to tighten the drive belts further.

remove the alternator, power steering and fan belts as they will no effect you car when engine is just running, the water pump runs of the timing belt, if it still squeals it you water pump.

readjust belt

If your belts are squealing it is the drive belt/belts that need attention not the timing belt. You need to check your belt tension and condition and replace as needed. If a timing belt ever got to the point that it might squeal the car would not run because it would be too far out of time. Your belts will all be external whereas at timing belt is internal and a major part of the engine.

If this is a front wheel drive car I would look at the CV joints

Check and tighten your drive belts / fan belts. The noise you are most likely hearing is the belt slipping on the alternator pulley. Its worse in the morning because the starter takes more out of the battery when the engine is cold. This in turn leaves the alternator with more load to replenish charge. More load = more resistance on the pulley to turn, hence the belt slips if too loose.
Cheers John