Oil temp gauge, soars at idle

[Akedas]

95 tsi. At idle or a red light, car oil temp gauge literally maxes out, then drops to the halfway point as soon as I move. I understand the wind and air are cooling the car but it literally soars from halfway to maxed out on the gauge within 15 seconds. IS something needing to be replaced?

 

[Defiant]

Where did you mount the sender for your oil temp gauge?