When this happens it is typically because your antifreeze and water mix (coolant) isn't correct. You want 50% antifreeze and 50% water to create the right coolant mix. The antifreeze will keep the car running cool while the water allows it to stay warm enough to provide heat in your vehicle.
When you are sitting still the water pump isn't moving at full speed so the coolant isn't flowing through the radiator as fast and heats up a little more. As well, you are not moving so the coolant running through the radiator isn't being cooled by any forced air like it is when you are driving.
Bottom line, you need to add water to your radiator. If it is full then I would suggest getting it flushed and put the correct 50/50 mix in the vehicle. Whoever filled your coolant obviously used 100% antifreeze.
thermostat probably damaged or stuck....and worse case scenario....your heater core is going out.
Most likely it is a belt on your car. Usually the squeeling is from a loose belt while idling and will also make noises while driving.
you need to replace your heater core
Check the electric fan to see if it is working.
Possibly defective thermostat. It sounds like it is opening up a bit with increased pressure caused by higher engine revs - when idling, the pressure decreases and the thermostat valve closes. Just a thought, anyway.
Low coolant, failed thermostat, partially plugged heater core...............
Does it have a miss? check plugs and wires. Also a possibility of a bad throttle position sensor.
You have a bad blower resister..............
I noticed while driving my Impala the temps stays at the normal operating temp but while sitting still the car runs near hot. I don't believe my fans are turning on when they should and if this is the case how do I address it?
Only blows cold air with the a/c on while driving, your cooling fan or fan clutch is bad depending on the year, make and model.......... Only blows cold air with the heater on while driving, you will have a bad or broken internal a/c - heater control door.....
Stalling while driving may be caused by a collapsing or kinked neoprene fuel line.
Yo have a boken termostat or yours has ben removed