The month of March is a transitional month. It’s when winter officially ends and spring begins (March 19th, this year)! However, those changes mean we typically see a wide range of weather conditions and phenomenon during the month. Wild temperature swings can lead to a variety of precipitation falling from the sky. Two of those different kinds of precipitation: sleet and hail. Some people wonder, what’s the big difference between the two?
Let’s start with sleet, typically thought of as a “winter time” type of precipitation. Technically, it’s more of a cold temperature type of precipitation. Sleet forms when frozen precipitation begins to fall through a warm layer of air and begins to melt, but then hits a layer of cold air closer to the surface. The partially melted droplet then freezes quickly before it hits the ground. If the air was cold the whole way down, it’d be a snowflake and if it was warm the whole way down, it’d be a raindrop. But because of the temperature changes, we end up with sleet! Sleet is also usually small.
When it comes to hail, it’s a whole different ball game. Hail is associated with thunderstorms. Thunderstorms form because of warm updrafts and when those updrafts become strong enough, raindrops in a storm will be pushed higher into the storm where temperatures are below freezing. Those frozen droplets are now hail and start to fall again. As it falls, it collects more water from other raindrops and can be pushed back up into the freezing layer if the updraft is strong enough. The collected water freezes again and forms another layer of ice, which is why you can see hail stones with distinct “rings” of ice. Once the hail is heavy enough or the updraft weak enough, it falls through the storm and then we see the hail reach the surface. As we know, hail can come in all different shapes and sizes.