Did you know that not all snowfall is created equally? Snow depths can vary greatly, and one of the reasons for this is the snow ratio.

When meteorologists talk about snow ratio, they’re describing the relationship between how much snow falls compared to how much liquid water it contains when melted. The standard ratio many people hear, 10 to 1, means that 10 inches of snow would melt down to about one inch of water. But in reality, that ratio can vary widely depending on temperature, humidity, and the type of storm producing the snow.

Warmer, wetter storms often create heavy, dense snow with lower ratios, sometimes as low as 5:1 or 8:1. That kind of snow packs easily and is great for snowmen and snowball fights, but tough for shoveling.

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Colder storms, on the other hand, tend to produce light, fluffy snow with higher ratios, like 15:1 or even 20:1, because colder air can’t hold as much moisture, and the flakes form as delicate, airy crystals.

Knowing the snow ratio is crucial for forecasting. A storm that looks like it will produce an inch of liquid precipitation could mean anywhere from a few inches to more than a foot of snow, depending on that ratio. So when forecasters talk about snow ratios, they’re really talking about the character of the snow, whether it’ll be the heavy, back-breaking kind or the powdery, “shovel it with a broom” kind.

Jennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.