Winter officially arrives at 12:47 p.m., but it's been making its presence felt all weekend.

Light snow falling across Western Pennsylvania today has prompted the National Weather Service in Pittsburgh to issue a special weather statement effective through this afternoon for most of the region. Included in the area are Allegheny, Armstrong, Beaver, Butler, Clarion, Fayette, Forest, Greene, Indiana, Jefferson, Lawrence, Mercer, Venango, Washington and Westmoreland counties, where motorists are warned to be on the lookout for slippery spots.

Areas also covered by the statement are southeastern Ohio, northern West Virginia and Garrett County, Md.

The weather service said untreated roads might become snow covered and treacherous. Bridges, overpasses and elevated roadways could become icy.

Snow is expected to accumulate about an inch in most of the region.

Pedestrians also should be careful: Sidewalks still are icy after the snowfall over the weekend.

Check out the PG's weather page for the latest conditions and forecast. Commuters also can access the updated traffic conditions.

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