10:55am Winter Storm and Tornado Forecast Update

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Blizzard Conditions likely in Kansas
  • Heavy snow, high winds likely from central Great Plains to Midwest.
  • Chance of a tornado in Oklahoma and north Texas tonight. 
This is a difficult forecast because snow thunderstorms will occur. I'll explain below. 

Here is my general forecast of snowfall with this storm. Combined with wind gusts to 50 mph, blizzard conditions are likely, especially within 50 miles of I-35 in Kansas. Two things: the band could shift 30 miles north or south. I have also bumped up amounts a bit because of the snow thunderstorm potential. More below.

Snow thunderstorms are likely with this storm -- which can cause highly variable amounts -- even within a county. Below is an example of the HRRR model which is designed to be able to forecast thunderstorms. Normally, model snow forecasts look reasonably smooth. Look how "splotchy" these amounts appear (important: this model can overforecast amounts, don't take them literally).
The splotchiness comes from snow thunderstorms. The most likely area for snow thunderstorms is from north central Oklahoma to just east of Kansas City. While heavy snow will fall farther east, it appears thunderstorms will not be as much of a factor. 

It is likely there will be a period of freezing rain or sleet when the transition from rain to snow occurs. Here is a forecast map of amounts. There is a chance of power interruptions in southeast Kansas.

There will also be high winds. This is the forecast wind gust map for 8am Thursday. Gusts of 50 to 60 mph are possible, making blizzard conditions likely. Combined with moderate to heavy rates of snowfall, travel will be life-threatening. 

Forecast radar for 8am Thursday. Note: the area of light intensity snowfall will be somewhat larger than depicted.


Overnight Tornado Risk
The brown area has a significant chance of a tornado overnight. This includes Wichita Falls, Ardmore and Ada. Please make sure you have a way of receiving tornado warnings during the night. 

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