The range of outcomes on this some has widened somewhat … for the worse.
Here is the forecast snow from the GFS model: Slightly farther north with lighter amounts east of Interstate 135. The red area is 15″ or more!
And, the heavier snow from the North American Model:
One thing is clear: Southwest Kansas, the Oklahoma Panhandle, and the northern Texas Panhandle are going to get nailed. If you have travel plans on U.S. 400, U.S. 54, U.S. 83, or U.S. 50 in those areas you are going to have to go before the storm starts or wait. Given the more than 12″ of snow (with 15″ forecast in some spots by these models) roads will become impassible.
One way to reconcile the differences in all of the models is to use a probabilistic approach. Here is the probability of more than 4″ of snow with the storm for the period from 6pm Sunday evening to 6pm Tuesday evening:
The probability of 4″ or more is 70% or higher all the way east to I-35 from Emporia to the Oklahoma border and on I-135 from Wichita to just south of Salina.
To help you time your travels, here is the simulated winterized radar for 6pm Monday evening. The red echoes northwest of the 32° (thin blue) line is very heavy falling snow.
By 9am Tuesday morning, it is forecast to be snowing over most of northwest Oklahoma, central Kansas, and into northern Missouri.
Please factor this storm into your Christmas travel plans.