Freezing Rain Potential

Another shot of cold air for Wednesday but it'll be gone as quickly as it came, warmer weather returns for Christmas Day. As we see the temps increase, we'll also see the chance for precip. increase. And I hate to be a downer, but it looks like there is a slight chance for freezing rain in Southeast South Dakota, Southern Minnesota, Northern Iowa and Northern Nebraska for Christmas Day night. And you can thank the warm air for that... Here are a few things we look at as meteorologists to determine if freezing rain is going to be a possibility: I usually will look at the heights first, this particular model has the 540 height just around the Sisseton area around midnight between Christmas Day and the day after Christmas. Many meteorologists use the 540 line as a hint to check out what type of precipitation to expect. If the 540 line is to the South of the area, usually we'll see snow. If the 540 line is way to our North, we'll see rain, but if it's relatively close, we need to look into some other things to see if there's the chance for freezing rain or sleet, etc.This is usually the thing I'll check next as far as the potential for freezing rain goes. I look at how much precip. a particular area is supposed to get according to one model then look at what the temperature at 850mb is supposed to be and what the temperature at the surface is supposed to be. If the temperature at 850mb is below -3, usually we'll get snow as long as the surface temperature is below freezing. If that temp is warmer than that and the surface temperature is still below freezing, that's when the potential for freezing rain is really apparent. Thursday evening looks like the 850mb temp is -2 and the surface temp is 28, so that means we'll see any precip that does fall start off as rain and freeze as it gets to the surface.
I'll usually check this great product called Bufkit. The red area that I circled in yellow is where the chance for freezing rain exists, right around 7pm on Thursday.

Of course there are a whole lot of other factors we look into as meteorologists... right now it looks like we will have a pretty dry air mass sitting on top of us for Christmas Day, so the chance that any precip. will actually fall Christmas Day evening is slim right now, but this chance will help some snow showers early on Friday morning.

Every meteorologist has their own method for determining what type of precip. we'll see, maybe Cody will fill you in on his methods in the morning :)

~KDLT Meteorologist Jesse Ritka

P.S. If you aren't up on the weather vocabulary, here's a great site to give you the basics: http://www.theweatherprediction.com/jargon/