09 aveo temp gauge issue

I have a chevy aveo 2009. While idling the temp
gauge goes up like normal and starts blowing
warm air. When I start driving the gauge goes
down and starts blowing cooler and cooler air.
After about 10 min at max it is all the way back
down to the cold line. 5 manual transmission if
that makes a difference. Coolant is good and
clear tested at -30.