What temperature is displayed on the instrument panel?
generally, the thermo-syphon effect within the cooling system means that the top will be hot and bottom will be cold and the coolant circulates (with the assistance of a water pump) within the engine and ancillary items such as the heater.
Therefore the bottom hose should be a lot cooler than the top one.
If you measure with an infrared temperature gun, the temperature should fluctuate (without any sharp dips or peaks) throughout the engine.