Winter looks to return to the Bluegrass State late Tuesday. After raining most of the day on Tuesday a cold air mass is forecast to move in from the northeast. Depending on the timing this cold air could transform the rain into snow by early Wednesday morning before ending before 6 am EST. Tuesday morning temps will range from the mid-40s to mid-50s but fall as the day continues. The entire state should see temps in the low to mid-20s by Wednesday morning. Windchills Wednesday morning could be in the mid-teens for most of the state. Portions of eastern Kentucky will have windchills in the low 20s.

 

 

Temperature

 

 

Windchill

 

 

Now for the possible snow. Both of the mid-range models, European and GFS, are showing possible snow but for now, they are different on the amount and coverage of the snowfield.

 

The Euro is coming in with the heaviest possible accumulations confined to southeast Kentucky.

 

 

 

The GFS is showing a wider field of possible snow accumulations but both are pretty close on where the snow should fall.

 

 

 

In conclusion at this moment, there is a decent chance for some snow accumulations by midweek. The unanswered question to answer is how much? I will be refining my forecast as we get closer.

It appears that parts of Kentucky have a chance of receiving some accumulation snows Tuesday evening into early Wednesday morning. All of the models are in pretty much good agreement on the snow falling. They still differ on the possible accumulation amounts. First the radar data from the mid-range models European and GFS. The Euro is coming in showing lesser amounts of precipitation and accumulations. One thing to note on the snow accumulations. The Euro uses the 10:1 ratio which usually means that for every 10 inches of snow that falls equals 1 inch of liquid water.

 

The Euro Ohio Valley radar from 7 pm EST Tuesday to 7 am EST Wednesday morning.

 

 

One thing to note on the snow accumulations. The Euro uses the 10:1 ratio which usually means that for every 10 inches of snow that falls equals 1 inch of liquid water which is usually seen when the temperature is around 32 degrees.

 

The Euro snow accumulation map. It shows most of the heaviest accumulations confined to parts of southern and southeastern Kentucky.

 

 

Now for the other models. The NAM and GFS and GDPS or Canadian Model. I've added the Canadian model just for the possible snow accumulations. All three of these models use the Kuchera Snow Ratio. Which I've found to be more accurate than the 10:1 Snow Ratio.

 

First the radar data. Both the NAM and GFS are coming in with a wider precipitation field covering most if not all of Kentucky. The time period covered is the same as the one I used with the Euro.

 

The GFS Ohio Valley Radar

 

 

There is one difference between the Euro, GFS and the NAM. The Euro and GFS use a 6-hour difference between each frame. For instance the first frame I use for 7 pm EST. The next frame is 1 am EST. So 6 hours will past before the simulation will show what happens next. The NAM uses only a 3-hour difference for the same data. So the NAM will show more data.

 

The NAM Ohio Valley Radar

 

 

Now for what the Canadian, GFS and NAM are showing for possible snow accumulations. They all show much heavier possible snow accumulations than the Euro model. They also show a wider snow accumulation field with the NAM coming in with the largest field and heaviest accumulations. The Canadian matches somewhat with the European but is showing heavier possible accumulations.

 

 

Temperatures Wednesday morning will range from the teens to the mid-20s. This range includes all of the 4 models with the Canadian coming in with the coldest temperatures.

 

 

 

In conclusion, it appears than something will happen Tuesday night into early Wednesday morning. It is too early to predict where and how much snow will fall. I should be able to get a good idea by this evening or at the very latest early Monday morning. So check back for updates