The engine works hard and produces a lot more heat than when the car is driven on a leveled road. The car is usually driven slower on the uphill and there isn't as much air cooling the radiator. But the main reason it overheats is that the cooling system is malfunctioning.
Generally, if your car overheats with the proper level of antifreeze, either your water pump has gone bad (not circulating fluid), the thermostat is stuck, or your radiator is clogged up inside. -NAPAman
Your car is starting to overheat or your thermostat is going out. Get it checked.
Each car overheats at a different temperature you need to look up and find out on the internet
your car overheats. Your oil is not going through the cylinders creating lots of heat
Worst case scenario--the engine has seized and you are going to be buying a new one.
Electric fan or fan clutch has failed.
your car will overheat, there will be low pressure on your system.
It usually catches on fire as seen at Monaco with one of the Marussia's. It can happen when the car is stationary for too long as they have no fans. Only air cooled radiators. The engineers can see the data so they may ask to save the engine before it damages itself but it really depends how quickly it does overheat. When the car overheats, damage can be done to fuel lines, exhaust systems and even the pistons.
YES
I have no idea what would cause a car to overheat emitting dense steam. When a car overheats, the first thing I check is the thermostat. When a car emits steam, I look for the place where the steam is coming from. I usually think two different problems are happening at the same time.
check egr valve