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Afternoon Sleet? Yes. Sleet. (Not Hail)

@Klappermom is the latest #tSpotter hero. She sent in this linked video, which for whatever reason we can’t embed, so here it is (http://www.mobypicture.com/user/klappermom/view/15059695). Turn up the sound!

Why’d it sleet this afternoon when it was 50 degrees at the surface? ¬†Keep in mind that it’s almost always colder the further up in the sky you go, and that’s what the precip is falling through on its way to you on the ground. When it’s really cold up there, the precip may go from snow, to sleet, and then to rain.

This graphic helps illustrate the point, even though it’s not exactly our situation.

What’s happening today is that the air near the ground is very dry. When the precip falls toward the ground, some of it evaporates. That process cools the air around it, lowering the temp for the precip that doesn’t evaporate, causing the sleet.

Hail happens as a result of usually warm weather convective thunderstorms with a strong updrafts and downdrafts. Rain tries to fall to the ground, but the updraft winds keep it suspended in the cold air aloft. The longer it’s suspended, the bigger the hailstones get, until they get so big they fall, or they’re transported to the downdraft part of the storm and fall to the ground. Science!

Categories: Uncategorized