About two inches of snow is expected to fall in Allegheny County by noon Thursday, the National Weather Service said.
An inch will fall overnight, meteorologist Bob Coblentz said, and another will fall between daybreak and noon. The temperature will fall to about 25 tonight and reach 33 on Thursday.
Visibility could be an issue for commuters.
"Anytime you have any snow at all, it's going to affect travel," Mr. Coblentz said.
Lexi Belculfine: firstname.lastname@example.org or 412-263-1878. Twitter: @LexiBelc.