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PITTSBURGH (KDKA/AP) – A winter storm is causing trouble on roads across western Pennsylvania.

The westbound lanes of the Pennsylvania Turnpike had to be blocked off at mile marker 111.6, near Somerset, on Tuesday afternoon.

A tractor-trailer was blocking all lanes and traffic started backing up in that area.

(Photo Courtesy: Bill Csaszar)

Earlier, Turnpike officials said certain vehicles would be banned as of 8 p.m. Tuesday. Those vehicles include empty straight CDL-weighted trucks, double trailers, tractors hauling empty trailers, and any trailers pulled by motorcycles, passenger vehicles, pickup trucks or sport utility vehicles. Also banned as of 8 p.m. Tuesday are all motorcycles and all recreational vehicles.

Turnpike officials said a comprehensive commercial vehicle ban or speed restrictions could be imposed as storm conditions develop.

PennDOT also closed a section of Route 30 in both directions in Somerset and Westmoreland counties, due to jackknifed tractor-trailers.

The road was shut down from the intersection of Nature Run Road in Ligonier, to the intersection of Route 985 and Somerset Pike in Jennerstown.

In Fayette County, the eastbound lane of U.S. Route 40 was closed between Hopwood and Jumonville Road.

According to PennDOT, multiple tractor-trailers became stuck on a steep grade. The road was closed until the trucks were removed. It has since been reopened.

“It gets real slippery up there being that it is the mountain. You have to travel up that large mountain to get up there, even thought it may be snowing or raining down at the bottom, it’s pretty heavy snow up top,” said Trooper Robert Broadwater, of Pennsylvania State Police.

A Winter Weather Advisory will be in effect from 8 p.m. Tuesday through 8 p.m. Wednesday as much of the area can expect to see about 4 to 6 inches of accumulation.

Drivers can also expect to see slippery conditions during the Wednesday morning commute.

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