[5:40 p.m.]: Motorists should expect icy conditions on metro Atlanta roads Saturday morning as the effects of the winter storm linger.

Georgia Department of Transportation spokeswoman Natalie Dale said crews will start spreading brine on interstate highways at 7 p.m. this evening and work overnight. They’ll also apply rock salt on secondary highways and will plow state roads as needed.

Dale said the agency has “all hands on deck from the metro area north.”

“Tomorrow, our biggest concern is black ice,” she said.

Dale urged motorists to stay off the roads Saturday, if possible. That’s partly for their own safety and partly to make it easier for GDOT to clear the roads.

[5:20 p.m.]: Rush hour is nearly over in many parts of metro Atlanta.

Traffic is still creeping along at less than 30 mph in spots. But traffic is moving on the Perimeter and on most interstate highways.

I-20 west of the city remains a trouble spot. Parts of Ga. 400 and I-75 north and south of the city also remain congested.

[4:30 p.m.]: The worst of the evening commute appears to be over — at about the time it would normally be in full swing.

Traffic headed southbound on the east side of the Perimeter is still creeping along at less than 30 mph. But southbound traffic on the west side is beginning to lighten. Parts of I-75 and I-85 north of the city are still congested, though traffic appears to be easing.

Traffic on I-20 also appears to be easing. Southbound I-75 south of Atlanta is congested near the I-675 split.

[4:22 p.m.]: A crash on I-75 South at Moores Mill Road temporarily blocked all lanes. It involved an Atlanta police car that arrived on the scene of a traffic accident, police Sgt. John Chafee said. The patrol car was struck by a box truck and another vehicle also was hit. The officer, who complained of back and leg pain, and a female from another vehicle were taken to Grady Memorial Hospital.

The ride on I-75 North from downtown to Cobb County, however, has lightened, Mark Arum reported.

[4:17 p.m.]: MARTA rail service experienced delays earlier this afternoon, but trains are now running at their normal frequency.

But the agency advises: “Our trains are packed and unable to board all waiting passengers at the stations right now.

“Various buses, depending upon traffic and route, are being severely delayed.”

[3:55 p.m.]: The Georgia DOT has about 800 people on call to deal with snow-related issues, spokeswoman Natalie Dale told Channel 2 Action News.

[3:45 p.m.]: "Think of it as a typical wet Friday drive," traffic reporter Mark Arum of News 95.5 and AM 750 WSB said of the interstates.

Also: CobbLinc announced it will suspend all bus service at 8 p.m. today. Service will resume sometime Saturday afternoon.

[3:11 p.m.]: A crash on I-20 East at Martin Luther King Jr. Boulevard has three left lanes blocked, according to the WSB 24-hour Traffic Center.

[3 p.m.]: Despite today's early commute, most roads in metro Atlanta are in good shape, according to the Georgia Department of Transportation.

“The interstates are great,” GDOT spokeswoman Natalie Dale said. “The (traffic) map looks scary, but it’s really (traffic) volume. We’re really dealing with high volume right now.

“We’re just dealing with a really condensed, heavy commute,” she said.

Some schools and government offices closed early, touching off the early traffic jam.

Dale said GDOT will apply another layer of brine to interstate highways tonight. The brine is used to prevent roads from icing over.

Average speeds are still below 30 mph on much of the northern half of the Perimeter and parts of I-75 and I-85 north of the city.

[2:10 p.m.]: The City of Atlanta has temporarily suspended Atlanta Streetcar service because of the weather.

ORIGINAL STORY: Rush hour came early to metro Atlanta on Friday, with slushy highways clogged with motorists scrambling to get home amid a mix of rain and snow.

Schools and government offices were closing early. By 1 p.m., traffic was crawling on interstates across the region. Traffic on much of the Perimeter, I-75, I-85 and Ga. 400 was moving at less than 30 mph.

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The AJC's David Wickert keeps you updated on the latest in what's happening with transportation in metro Atlanta and Georgia. You'll find more on myAJC.com, including these stories:

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