What Temperature Is Rain?

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Does rain make you feel cold? The reason why isn't just because it moistens your clothes and skin. The temperature of the rainwater itself is also to blame.

And just what temperature is rain? On average, raindrops have temperatures somewhere between 32 °F (0 °C) and 80 °F (27 °C). Whether a raindrop is closer to the cold or warm end of that range depends on a number of things, including what temperature it starts at high up in the clouds, and also what the air temperatures are in the upper atmosphere where those clouds are floating.

As you can imagine, both of these things vary from day to day, season to season, and location to location...which means there is no "usual" temperature for raindrops. 

Let's explore how temperatures in the atmosphere interact with a raindrop, starting from its birth high up in a cloud to its final target—you and the ground.

Rain Is Often Cool Because It Begins as Snow

Surprisingly, most of the world's rainfall begins as snow high up in the clouds overhead—even on a hot summer day! That's because temperatures in the upper portions of clouds are well below freezing, sometimes as low as -58 °F ( C). The snowflakes and ice crystals found in clouds at these cold temperatures and heights warm and melt into liquid water as they pass below the freezing level, then exit the parent cloud and enter the warmer air below it.

The Act of Falling Through Air Cools Raindrops Even More

As the melted raindrops continue to descend, they can become cooler through evaporation.

This process (which meteorologists call "evaporative cooling") happens like this: As rain falls into drier air it causes that air's dewpoint to increase and its temperature to lower. This is also one reason why rainfall is associated with cooler air. (It also explains why meteorologists sometimes claim it is raining or snowing high up in the upper atmosphere, and will soon do so out your window—the longer this happens, the more the air near the ground will moisten and cool, allowing the precipitation a path to fall to the surface.)

Air Temperatures 10,000 ft Above Ground are Critical to Final Raindrop Temp

In general, as precipitation nears the ground, the atmosphere's temperature profile (the range of air temperatures that the precipitation passes through) from around the 700 millibar level down to the surface determines the type of precipitation (rain, snow, sleet, or freezing rain) that will reach the ground. If this temperature is above freezing, the precipitation will, of course, be rain, but how warm above freezing they are will determine how cool the raindrops will be once they hit the ground.

Ever experienced a rain shower that was actually warm to the touch? When raindrops feel warm to our skin it means that their temperature is above the current surface air temperature. This occurs when temperatures from 700 millibars (3,000 meters) down are quite warm, but a shallow layer of cooler air blankets the surface.

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Means, Tiffany. "What Temperature Is Rain?" ThoughtCo, Dec. 2, 2016, thoughtco.com/what-determines-rain-temperature-3443616. Means, Tiffany. (2016, December 2). What Temperature Is Rain? Retrieved from https://www.thoughtco.com/what-determines-rain-temperature-3443616 Means, Tiffany. "What Temperature Is Rain?" ThoughtCo. https://www.thoughtco.com/what-determines-rain-temperature-3443616 (accessed September 21, 2017).