As Cold Air Invades U.S., Odd Big Snowstorms Loom Around Chicago, And Southern Appalachians

Web cam grab from Chicago this morning showing
light snow falling. Blinding snow squalls are expected
tonight and tomorrow, which will cause serious 
travel trouble, and tree and power line damage. 
Another snowstorm will also hit high
elevations of the southern and central
Appalachians. 

 It's a little early in the season for massive snowstorms in most of the United States, but a couple of them are in the forecast.  

Areas in and around Chicago, and the southern and central Appalachians are about to get blasted by some big, brutal snows.  

The overall blame goes to an unusually strong cold snap smashing into the eastern half of the United States. There are no big storm systems accompanying this frigid blast. But some local effects are creating two big autumn snowstorms.  

CHICAGO/ENVIRONS

A pretty dire winter storm warning has been issued for the Chicago area, and northern Indiana tonight and early Monday. 

The cold air is sweeping into the Midwest on north winds. Those north winds are running down the length of still relatively warm Lake Michigan.  That's a long fetch down the length of the lake.  A great opportunity for the cold air to collect moisture from the still-relatively warm lake. 

It's a perfect setup for lake effect snows.

An initial lake effect snow band hit Chicago this morning, but it was just a tease before the main event. This morning's snow was enough to create delays at Chicago's O'Hare airport. 

The real show gets underway overnight and on Monday. . 

 The winter storm warning calls for "dangerous to impossible travel conditions" due to intense lake effect snow. In some spots, snow could fall at a rate of three inches per hour with local accumulations of 12 to 18 inches. Winds could gust over 30 mph, so they can expect blowing and drifting snow.  The intense snows might also be punctuated by thunder and lighting. 

Until now, it's been a rather warm autumn in Chicago. Some of the trees still have leaves on them. The snow will accumulate on those leaves and pull branches down. Expected strong, gusty winds won't help.  All that would cause a lot of power outages. Chicago might end up with a bunch of damaged homes and other buildings as snow laden trees and large branches crash onto and through roofs. 

Lake effect snow bands are usually narrow, so some areas in and near Chicago will get blitzed, and others won't be hit quite as bad. The worst of it will hit before and during the morning commute, so things could get really interesting on the roads and streets Monday morning.  

The exact placement of lake affects snows are hard to predict.  For now, it looks like the one expected to hit Chicago might wane during the day Monday. But then, another, perhaps stronger snow band off Lake Michigan could plow into northern Indiana, in places like Gary and South Bend tomorrow afternoon and evening. 

I'm guessing places from Chicago to South Bend could have their deepest snow for so early in the season by tomorrow.  

APPALACHIANS

Pretty much the entire Appalachian chain from Georgia to Maine will see some snow out of this cold outbreak. Parts of the southern and central Appalachians might really get nailed. 

The heaviest snow will be limited to the highest elevations. In western North Carolina and eastern Tennessee above Gatlinburg, three to seven inches of snow is forecast above 3,500 feet and 10 inches or more could come down at summit level.  

That kind of snowstorm happens from time to time in these mountains  but the first half of November is awfully early for such a snowstorm.  

Snow showers will extend all the way down to valley floors around Asheville, North Carolina.

Further north, another winter storm warning is in effect for the mountains of eastern West Virginia. Those areas could see seven or more inches of snow. Wind gusts of 40 mph or more combined with the snow might bring down trees and power lines. 

Several inches of snow is also likely in the northern Appalachians, especially through New England. That far north, such high elevation snowfalls are pretty common this time of year. 

In Illinois, Indiana and the Appalachians, temperatures are forecast to go back to near seasonable levels by the middle of this week. That should melt the early season snow. Then they can safely wait until winter really hits.