Weather Academy: Snowfall Explained

MONROE, La. (KNOE) - This week, we are talking about my favorite type of precipitation, snowfall! Typically here in the ArkLaMiss, we see snow once or twice a year, but it doesn’t like to stick. However, we see plenty of the other types of winter precipitation. So let’s dive into the science behind snowfall.

Everything starts as snowfall as ice crystals fall from the clouds. When the ice crystal runs into warmer air, it melts and falls to the ground as rain. During the winter months, we can get a layer of colder air developing at the surface. So our ice crystal will melt as it runs into warm air and fall to the ground as a raindrop, only to freeze as soon as it hits the surface. Freezing rain is the most dangerous form of winter weather as it can cause road conditions to be treacherous, similar to the 2021 Ice Storm we experienced last February. When that section of warm air starts to shrink, we will see sleet. Sleet will fall to the ground as tiny ice pellets. Basically, they are frozen raindrops. When the column of air is entirely below freezing, that’s when we see snowfall.

There are a lot of factors that go into forecasting snowfall. The main thing we need to worry about is the temperature. Generally, colder temperatures will lead to fluffier, deeper snow. Colder ground temperatures can also be a factor. Think about the snow we saw here in the ArkLaMiss a few weeks ago. Our ground temperatures we relatively warm, so the snow melted as soon as it reached the surface. With colder surface temperatures, the snowfall will accumulate and pile up immediately. Lighter winds will also lead to high snowfall accumulations. Stronger winds will break up the snow and cause it to become compact.

But let’s focus on the importance of temperature for a second. One inch of rainfall will typically produce 10 inches of snow when the temperature is 32 degrees. When we are sitting right at freezing, we usually see wet, heavy snowfall. The snowflakes are sticking together because they are right at the melting point. This snow is good for building snowman because it sticks together well but is less in terms of accumulation because it is so heavy it becomes compact. At 25 degrees, that same one inch of rainfall could produce up to 15 inches of snow because the colder temperatures will cause lighter, fluffier snow to fall. At 20 degrees, we will see fluffy powdery snow. This is the type of snow that is perfect for skiing and snowboarding.

We might not see a lot of snow here in the ArkLaMiss, but that won’t stop us from trying to have some wintery fun. Make sure you tune in next week because Sheena and I will be making our own snow.

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