Thermostat or water pump
 

So for the past while my engine temp has been going a little higher than usual before it jumps back to where it normally is. In the past I have replaced my thermostat and had the same problem go away.

Today however I was driving and the engine temp goes almost to the red and the voltometer starts to go down then there is some belt squeal and the voltometer goes back to normal and the engine temp goes back to normal.

the car has 141k on it sound like a water pump to me I just need someone to back me up of give me another cause

If the belt squealed and the volts went down with the temp going up, then I would look at and possibly depending on the belts condition replace the belt not the pump. Unless the pump is locking up from bearing failure then that would cause that.

I would take the belt off, inspect it, and turn the water pump by hand and see if its hard to turn, which means the bearings are failing.

Yeah, more than likely a belt, BUT it could be possible that the water pumps locking up as well. The reason your volts went down is because something made your alternator stop turning slightly, water pump couldve locked up or something, or the belt couldve been slipping. Also theres the chance that it may be another pulley causing the belt to have slowdown.

true, make sure your tensioner isnt worn out releiving pressure on the belt causing it to slip