Intermittent grinding noise from left front

I'm trying to get my Jeep ready for the warm weather that's coming, so I fired it up and took it around the block last night and noticed a grinding sound coming from the left front wheel area. Does anyone know what this might be? Bad bearings? Hub? What would be the easiest way to determine what the problem is so I can get to work on it?

 

move the vehicle back and forth and have someone listen for the noise. Or take it apart and inspect the bearings, axle u-joints, etc.

 

I know it is coming from this area because if you jack it up and spin the wheel, you can hear it. Could it possibly be the brakes grabbing? It sounds more serious than this though. Definite grindage! I'll probably start pulling it apart tonight and have a look.