Winter precipitation explained

By Justin Logan - bio | email feedback

Jonesboro, AR (KAIT) - Winter in Region 8 can bring just about anything from sleet and snow to freezing rain. We all know what snow is, but the difference between freezing rain and sleet are often confused.

First of all we have to look at the atmosphere from top to bottom to see the process. All precipitation begins in frozen form but after that is when the changes occur.

For freezing rain you need to have several things in place. It begins as snow in a cold layer of air at the top of the atmosphere. Then once the frozen precipitation makes it down into warmer air, which is above freezing, it turns over to all rain.

Once the rain gets back down to the surface, there is a shallow layer of colder air (at or below freezing) and the precipitation freezes on contact. That's when we see the ice collect on everything which is what we saw last year during our ice storm.

Sleet on the other hand is a different scenario. Precipitation first starts as snow then it partially melts when it passes through a warmer layer of air. Then the partially melted snow falls through a deep layer of cold air (below freezing) and we get sleet (ice pellets) which are frozen raindrops.

For snow to occur we need below freezing temperatures from the top of the atmosphere down to almost the surface. However, we can still get snow with surface temperatures above freezing. There is a simple reason for that, the snow doesn't have enough time to melt.

Why is this important? Well, each of these can pose a different hazard. Freezing rain sticks to everything causing power outages and making travel almost impossible. While sleet and snow both cause slick travel, snow can be shoveled making it easier to deal with.

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