Allegheny County and several others in Western and south central Pennsylvania are under a winter weather advisory, per the National Weather Service.
The advisory is in effect from 7 tonight to 10 a.m. Wednesday and calls for up to 2 inches of snow along with sleet and freezing rain in Pittsburgh.
The National Weather Service said that as of 8 tonight, freezing rain and sleet had begun south of Pittsburgh, causing a small amount of ice to form. The system is expected to spread north and cross Allegheny County between 9 and 10:30 p.m. No snow has accumulated thus far, according to the National Weather Service.
The city Public Works Department issued a Phase 1 alert, saying it expected road conditions to worsen between 9 p.m. and midnight. It warned of possible snow- and ice-covered streets and freezing of ramps and bridges.
Pennsylvania Department of Transportation winter maintenance crews began pre-treating roads this afternoon and evening, it said in a press release.
PennDOT urges motorists to "to use caution and slow down, particularly on bridges, ramps and overpasses which can freeze faster than roadways," it said.
An ice storm warning has been issued for the following counties: Garrett, Md., and Tucker, W.Va.
The winter weather advisory is in effect for Armstrong, Beaver, Butler, Clarion, Fayette, Indiana, Lawrence, Washington and Westmoreland counties, east central Ohio and parts of western Maryland and West Virginia.
Lexi Belculfine: email@example.com or 412-263-1878. Twitter: @LexiBelc. Jon Schmitz: firstname.lastname@example.org, 412-263-1868 and on Twitter: @pgtraffic. First Published January 15, 2013 7:30 AM