The quick snow accumulation turned the parkways, the Pennsylvania Turnpike and many other roads into a melange of crashes, stuck vehicles and stopped traffic.
The wet, heavy snow turned to hardened slush when driven or walked upon, making streets and sidewalks treacherous. Salt trucks and plows became mired in traffic, unable to make their rounds.
Pittsburgh Public Works Director Rob Kaczorowski said his team has 50 pieces of equipment salting and plowing roads. And PennDOT trucks worked in tandem on Interstate 79 southbound.
"The best thing for people to do is stay home," he said.
PennDOT pre-treated all interstates in Allegheny County and Routes 28 and 65 this morning. New PennDOT crews coming on at noon will work a 12-hour shift -- and those coming in at midnight will also work a 12-hour shift.
PennDOT has 65 of its own trucks and 15 rented trucks treating roadways, spokesman Steve Cowan said.
"In storms of this nature, the goal is to keep the roadways passable -- not completely free of snow and ice," he said. "When it's coming down that quickly, it's near impossible to keep it free of snow and ice."
Some snow and freezing rain is expected overnight, but meteorologists don't expect much of it to accumulate.
People living near the Interstate 80 corridor might see another inch or two of snow, but most others in Western Pennsylvania will see less than an additional inch, said Tom Green, a meteorologist with the National Weather Service in Moon.
Driving conditions are preventing Port Authority buses from making their way through the Hill District tonight.
"We've experienced similar issues through the day, including a period when we couldn't serve Mt. Washington," spokesman Jim Ritchie said in an email. "We know crews are working hard to get to secondary streets tonight."
Mayor Luke Ravenstahl has spent part of the day working from home and part of the time riding around city streets to inspect conditions, spokeswoman Joanna Doven said. She said public works crews are working overtime on snow removal but noted, "Everyone needs a plow on their street at the same minute."
At 3:45 p.m. Public Works Director Rob Kaczorowski said that 70 percent of primary roads are clear or passable and that 20 percent of secondary roads are passable. He said all public works districts should be at those levels, even in the East End. By 6 p.m., weather permitting, crews should be able to focus all of their attention on secondary streets.
Asked about the storm response shortly before 4 p.m., Mr. Ravenstahl said, "It's getting there."
Problems on interstate highways, he said, give some indication of challenges the city has faced with miles of hilly streets.
"The trucks are out there," he said during a brief interview at city hall. "I've seen them out there. The good news is, the snow has stopped."
City Councilman Bill Peduto, who will challenge Mr. Ravenstahl in next year's election, said he had driven on every primary road in his council district today.
He estimated that 75 percent to 80 percent or primary roads were passable by 3 p.m. He said that's not good enough considering the amount of snow the city received and the advance warning that officials had.
"The primary roads should be done by now," said Mr. Peduto, who tweeted road conditions throughout the afternoon.
Snow-clearing efforts were uneven, Mr. Peduto said, saying primary streets in the Bloomfield, East Liberty and Shadyside areas were in much better shape than primary streets in Point Breeze and Squirrel Hill. In fact, he said some secondary streets in Shadyside were in better shape than primary streets, such as parts of Beechwood Boulevard and Forbes and Shady avenues, in Squirrel Hill.
Lots of crashes, some roads impassable
Roads were a mess in much of the region for much of the day.
Cars moved cautiously along snow-covered Liberty Avenue and Penn Avenue between Downtown and the East End.
Toni Johnson waited 30 minutes to catch a bus near the Consol Energy Center before deciding to hike to the Wood Street station around noon.
The 67-year-old grandmother braved the frosty conditions to pick up a medication for her grandson at Children's Hospital. Keyshawn, 9, has sickle-cell disease and requires two doses daily of a liquid medication that was accidentally spilled over the Christmas holiday.
"The weather doesn't bother me, but if the city knew this was coming they should have cleared the streets," she said as she rode the 88 bus headed Downtown around 1:40 p.m.
Ms. Johnson said she only went outside because her trip was a necessity.
"I'm not coming back out," she said. "If it was not for this, I would not have be out at all."
Route 28 was closed for more than an hour in both directions near Harmar and Tarentum but has since reopened.
Route 8 northbound was wet-to-slushy around 3:30 p.m.; southbound was snow-covered. There were many problems with trucks having no traction on hills, blocking traffic behind.
A tractor-trailer slid off the outbound Parkway West near Banksville Road, causing its closure for more than an hour.
A car flipped onto its side on the inbound Parkway North before the Camp Horne Road exit. Several cars slid into one another on the inbound Parkway East near Churchill. Three vehicles collided in the outbound Liberty Tunnels.
A crash on northbound Interstate 79 near Kirwan Heights backed traffic to the Washington County line. Crashes also were reported on outbound Route 28 near the Highland Park Bridge, at the Route 51-Lebanon Church Road cloverleaf in Pleasant Hills and Route 88 at Connor Road in Bethel Park.
Nearly 200 miles of the toll road, stretching from Ohio to just west of Harrisburg, quickly became snow covered.
A crash on the turnpike between Donegal and Somerset blocked the highway, causing traffic to back up for more than a mile. The turnpike also reported a crash eastbound between Irwin and New Stanton.
Turnpike officials lowered the speed limit to 45 mph for 298 miles from Ohio east to the Morgantown Interchange and banned empty tractor-trailers from New Stanton to Breezewood.
Pittsburgh police were stretched thin responding to vehicles stuck on hills. Chatter on emergency dispatch radio channels indicated conditions were so treacherous that some city medics were having difficulty getting to weather-related and other medical calls. Some EMS vehicles got stuck and requested tows.
A car rammed a fire hydrant at Liberty Avenue and 22nd Street in the Strip District, shearing it off. Herron Avenue near Bigelow Boulevard was closed as impassable.
Electrical service seemed to hold up well.
In Bullskin, Fayette County, a downed tree knocked out power to 161 West Penn Power customers for a few hours this afternoon. Terri Knupp, a spokeswoman for the company, said service was restored about 4 p.m.
Joe Vallarian, a spokesman for Duquesne Light Company, said there were no outages to report in Pittsburgh or the surrounding area.
Public transit services also impacted
The snow, the traffic and impassable roads were playing havoc with Port Authority transit service as well.
"It's pretty simple: delays across the board," spokesman Jim Ritchie said.
Port Authority bus service is running 30-plus minutes behind schedule throughout Allegheny County this afternoon due to poor weather and road conditions, Mr. Ritchie said. Riders should plan accordingly and anticipate significant delays today.
Light rail service is not significantly delayed, he said.
"The simple message is, it's winter weather, it varies community to community," Mr. Ritchie said. "You should expect delays, plan accordingly and don't go out if you don't need to."
A broken-down rail vehicle caused delays on the Red Line and a switching problem caused delays at Allegheny Station on the Light Rail Transit system this morning.
Mr. Ritchie said rail operations were expected to be normal this afternoon.
Airport delays expected
FlightStats.com counted 66 canceled arriving and departing flights at Pittsburgh International Airport.
PIT is not under a Federal Aviation Administration airport delay, though some flights from other airports to Pittsburgh may be delayed or canceled, airport spokeswoman JoAnn Jenny said.
"The odds are pretty good there will be a number of flights impacted by the weather," she said, noting roads to the Pittsburgh airport will likely be treacherous for travelers.
Those who want to re-book fights should do so as soon as possible, she said. Airlines won't charge fees to reschedule in inclement weather, Ms. Jenny said.
And more to come
National Weather Service meteorologist Lee Hendricks said the storm is "nothing out of the ordinary, pretty much a standard storm" but was troublesome nonetheless.
"Pretty much if you go from Beaver to Allegheny, Westmoreland and Fayette counties and points north and about halfway down the northern panhandle [of West Virginia], it's primarily snow falling but in the past hour we've had reports of periods of snow mixed in with sleet," he said at about noon. "Further south, in Washington County, earlier it was sleet and freezing rain that then switched to snow and now is back to sleet and freezing rain."
The precipitation in whatever form is creating treacherous travel conditions.
The weather service said total snowfall of from 3 to 6 inches is predicted by 6 p.m. in Allegheny County with 6 to 8 inches predicted in Butler, Indiana and Lawrence counties and upward to 10 inches in northern Butler, Clarion, Forest and Jefferson counties. Winds are 15 to 20 mph with gusts to 35 mph, so there is blowing and drifting of snow as well.
"Rush hour should be an adventure," Mr. Hendricks said. "For as heavy as the precipitation is coming down and the wind is blowing the snow around, it's going to cause challenges for road crews. In the areas where there was freezing rain and sleet with snow now on top of that, it's going to make conditions even more treacherous and more challenging for road crews. If you don't have to travel, it's probably best not to. If you have to, leave early and take your time."
Overnight, gusty winds will create hazards of blowing and drifting snow but by tomorrow, there will only be some isolated freezing drizzle with a 40 percent chance of snow showers and no accumulation.
Some took the snow and the forecast as a sign -- to buy tires. Immediately.
By noon, Goodyear in Cranberry Township had already reached its average daily tire sales, according to sales manager Brian Cooper. An afternoon tire delivery had been canceled, rescheduling some appointments.
About 2 p.m., the phone quieted and only a few people were waiting in the lobby.
"It was ringing nonstop," Mr. Cooper said.
He estimated about 95 percent of customers today came in for snow or all-weather tires -- about 20 cars since 7 a.m. -- but a few braved the weather for an oil change, he said.
Andrea Thews of Cranberry was en route to her noon shift at the T-Bone's Marketplace deli counter in Wexford today when her Hyundai Elantra got stuck in the snow outside her house.
She made it three miles to the Goodyear and was waiting for new front all-weather tires about 2 p.m.
"I've just been waiting to get them," she said. "I was hoping to catch a sale."
Some workers sent home early
At UPMC, the region's largest employer, some managers in business units allowed employees to leave early because of the inclement weather, spokeswoman Stephanie Stanley said.
The hospitals and clinical units have a severe weather policy to assure that those units would be adequately staffed but it did not have to be enacted today, she said.
Gov. Tom Corbett allowed state employees in the Capitol Complex, Harrisburg area, and offices in Pittsburgh, Reading, Scranton and Philadelphia to go home at 3 p.m. The Allegheny County Court of Common Pleas closed for the day and non-essential county employees were sent home at 2 p.m.
But even then, it was no easy thing.
Ms. Stanley hoped to catch the 56 Lincoln Place bus at 11:45 a.m. to get to her home in Hays.
The bus was nearly 90 minutes late because an accident on Dravosburg Hill had temporarily closed that roadway.
Once on the bus, traffic was light but the roads were in bad shape, she said. Her bus ride, which normally takes 20 minutes in rush hour, taking nearly twice that time in the early afternoon.
"It was a long haul getting home but I'm here now," she said.
She said she wouldn't venture back out again today.
Molly Born: email@example.com, 412-263-1944 and on Twitter: @borntolede. Joe Smydo and Liz Navratil contributed. First Published December 26, 2012 1:30 PM