'05 Honda Pilot Cooling Issue?

I have an '05 Honda Pilot that is experiencing the following symptoms:

1 - sound of liquid moving (coming from under the hood) when the vehicle is idle or in motion.
2 - temperature gauge on dash reading high when vehicle has been in idle for a while.
3 - sound of fans running (I think) under the hood after the vehicle has been turned off.

Any ideas?
I will take it in to a mechanic but would like to have some idea of what the issue might be first.

Thanks so much!!

This points to low coolant and air in the cooling system. The sound of liquid moving is the coolant going through your heater (heat exchanger) under your dash. Air bubbles are making the noise. The gauge reading high is probably due to low coolant, you are right on the edge where the car moving has enough outside air movement to cool the engine, but when stopped there is not enough coolant moving through the system to keep up and dissipate the heat. The fans running are trying to continue to cool the engine off. When the car is cold take the cap off the radiator and see if there is coolant visible, I bet there won’t be any. Get some from your local parts store and add it. If you have a reservoir, add it there too. You want to have a 50/50 mix. So add a cup or so at a time and alternate with a cup of filtered water. You probably have a leak in the cooling system, there could be other things causing it.