Good morning Weather2020 bloggers,

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A major winter storm is now developing and it is quite impressive. It is taking a track that would usually produce a foot of snow near Kansas Cit, however it is the 2015-2016 season version of a storm system and there is warmer air than what usually exists around a storm such as this. Where it snows it will be a lot. If you are in the transition zone, then sleet and freezing rain will cause significant problems.

Weather Forecast Time-Line For Kansas City:

  • Now to 7 PM tonight: Dry for the Chiefs game, but cold and windy!
  • 7 PM to 7 AM: Heavy rain, freezing rain, and sleet move in. Most of the precipitation is likely to be freezing rain or sleet. The snow line will be way out to the west and northwest. Some significant icing and sleet accumulation is likely. If it’s sleet there could be 1 to 3 inches of just sleet which would coat every surface. If it’s freezing rain, then there could be enough ice to cause power outages and other problems.
  • 7 AM to Noon Monday: Sleet or freezing rain continues that will gradually change to snow
  • Noon to 7 PM Monday: The mixture likely changes to snow with accumulations from 1 to 5″ possible depending on when it changes over, and this will come on top of sleet and freezing rain

I would like you to look at this surface map from this morning at 8:33 AM. There was an 87 degree contrast from eleven below in northwest Nebraska to 76 degrees at just after sunrise to the southeast. Wow is all I can say about this!

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We now can establish that this system has tremendous fuel to work with.

4The track is almost perfect. In any other year, if you told me it was near freezing and that an upper low this strong was taking a track like this, I would say did you get a foot of snow or more? But, this is an unusual year with El Niño at near record highs right now.  The low is forecast to track from near the Mexico border northeast to near Kirksville, MO by Monday night.

Warm air is being drawn in from the south and southeast.  This next map shows the 850 mb map, which is showing the conditions at around 5,000 feet above us.  When the temperatures at this level drop to below 0°C (32°F) it usually snows in KC if the surface temperature is near freezing. But, again, not this year and likely not this storm:

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Again, if you showed me the two maps above, then I would say “how much snow did you get”. Instead we have a long waiting game before any snow falls in KC. This surface map shows a lot:

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I hope I am not getting too complex today. This is not an easy one to explain.  Thickness is a measuring of a layer of the atmosphere  from 1000 mb to 500 mb, and when the layer is 5400 meters thick (a 540 thickness), then that layer is usually all below freezing and it snows in places like Kansas City. That critical thickness is higher for higher elevations like over western Kansas where they just need a 546 thickness for snow. As you can see on this map, our thickness, as of 9 AM Monday is forecast to be near 552 which is way to warm. This means that there is a layer around 7,000 to 10,000 feet up where the precipitation is forming that is above freezing. This means that the precipitation type will either be freezing rain, rain, or sleet in this area.

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Thunderstorms with sleet or snow are possible.  It could be a frustratingly long wait for that first big snowflake. It’s a fascinating storm. I hope this blog made sense. This is not an easy storm to describe. Have a great day, and I will leave you with this video! Thank you for participating in the LRC Forecast Experience Blog and let us know if you have any questions.

Gary