Weather Fundamentals


What is a triple point

The triple point is the temperature at which a substance can exist in equilibrium in all three of its states: gas, liquid, and solid. For pure water, the triple point—at an air pressure of 4.58 millimeters of mercury—is 32.018°F (0.01°C). The term “triple point,” however, can also refer to the spot where an occluded front meets a warm front.


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