Tuesday, December 23, 2014

Christmas Eve Snow?

We have gone back and forth on the chance of snow on Wednesday morning. I've tried to wishcast away the snow, but Winter may get the last laugh.

The data has been conflicting, but tonight most of the data agrees. And it agrees that it may snow Wednesday morning. Here are the bullet points as of Monday night at 11:45 PM:

  • Computer model data has been cruddy lately.
  • Despite that, I'm growing confident enough to mention some snow on Wednesday morning.
  • LIGHT accumulation is possible, mainly in higher elevations.
  • Jonesboro/Paragould areas will probably not see much.
  • Roads should be fine.
  • Temperatures will likely stay ABOVE Freezing.
The first question you probably have is ... how can it snow if I'm expecting temperatures to stay above freezing? Well, we are going to have some very cold air aloft. If the precipitation lingers around on Wednesday, it could be in the form of snow. Here is a forecast sounding for SHARP COUNTY. A forecast sounding shows the expected temperature and dewpoint as you go up through the atmosphere. The red line is the temperature and the green line is the dewpoint. Anything left of the blue line is freezing and anything to the right of the blue line is above freezing. Notice, at the surface we will be above freezing in Sharp County. BUT, only the lowest portion of the atmosphere will be above freezing. That's not enough time for the falling snowflakes to melt:
I'm not sure what that means for accumulations. That's the tricky part. If it comes down hard enough, it could stick. Even if it sticks, I doubt the roads would get covered.

Both the GFS and NAM data from this evening shows some light accumulation. This is the NAM model, but the GFS looks very similar:
While a dusting is not considered a White Christmas, the snow might help you get into the Christmas spirit. We are not officially putting out an accumulation forecast, yet. That will come tomorrow, if needed. The image you see above is just model data, but its data I felt confident enough in to post.

Have a great evening and look for updates tomorrow.

Ryan

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