The National Weather Service in Pittsburgh this afternoon issued a winter storm warning, increasing the potential amount of snow that is expected to start falling Friday afternoon.

The weather service, which had previously said 6 or more inches of snow was possible, now says 6 to 12 inches is possible between late Friday afternoon and 6 p.m. Saturday.

Snow is expected after 4 p.m. Friday, getting heavier Friday night and into Saturday, with the chance of precipitation 100 percent.

The warning suggests people travel only in emergencies.

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

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