Is My Car Running Hot or Gauge Not Correct?

I have a '96 LT4. I notice whenever I'm at a stop light (and outside weather makes no difference) my analog temperature gauge climbs almost to the max temperature. But as soon as I start to move, it goes back to normal. I don't think the car is overheating and it does not seem to be overheating. I thought maybe my gauge is not really working well.

Is anyone else seeing this same problem? Thanks in advance.