Two weeks after a snowstorm brought the metro area to a halt, another round of winter weather is on the way.

But this time, it’s not just the snow. It’s the ice that has forecasters and government leaders most concerned. And the worst of the storm may not roll through until Wednesday, according to chief meteorologist Glenn Burns with Channel 2 Action News.

“Do be prepared for massive power outages as this is likely to be a massive weather event,” Burns said Monday evening.

The evening commute started a little earlier than normal Monday afternoon, but metro interstates crawled at their normal slow-and-go pace despite the looming winter storm.

Instead of busy interstates, it was smaller side streets seeing heavier than normal traffic Monday afternoon, said Doug Turnbull, traffic reporter for WSB radio. Check the WSB traffic website for the latest information.

Shopping center parking lots were bustling throughout the day Monday, with many stocking up to prepare for possibly being stuck at home several days.

“Around 3 a.m., the first batch of wintry weather moves into west Georgia, moving eastward,” Channel 2 meteorologist Brad Nitz said.

What the forecast looks like

There is a 100 percent chance for precipitation early Tuesday, but the type of precipitation will vary depending on where you are in the metro area, Nitz said. A wintry mix including snow and rain is expected north of I-20, with accumulation possible northeast of Atlanta, he said. Areas south of town may only get rain.

The precipitation will taper off later in the day as temperatures reach only about 36 degrees, Nitz said. Late Tuesday, round two of the storm kicks in.

“We’re setting up for the potential of a major ice storm Tuesday night and into Wednesday,” Nitz said.

And that layer of ice is what has power companies worried. Ice can create enough weight to bring down both trees and power lines. Wednesday’s high temperature won’t climb above freezing.

The metro area could have between 24 and 30 hours of freezing rain, forecasters said.

Government agencies get busy

State agencies began preparing Sunday for the oncoming storm in hopes of avoiding the hours-long gridlock many Atlantans faced in January.

“I want to make sure that everybody stays safe and we keep the roads usable,” Mayor Kasim Reed said Monday night.

Late Monday morning, Gov. Nathan Deal expanded the weather-related state of emergency to 45 counties as another round of significant winter precipitation set its sights on parts of north and central Georgia.

Deal encouraged residents in the storm’s path to “be off the road by early evening” Monday as transportation crews prepare the roads. Deal also asked tractor-trailers, which caused mayhem during the January storm, to steer clear of I-285. The governor convened his emergency response team at 11 a.m. Monday, including executives from hospitals and utility companies. Deal said he was particularly worried about the “devastating” impact of ice dragging down power lines.

Crews working 12-hour shifts were preparing late Monday to use 125 pieces of equipment to begin spreading some 3,000 tons of de-icing materials, according to Richard Mendoza, commissioner of public works for Atlanta and Georgia.

Many school systems cancel classes

Late Monday afternoon, metro school systems announced plans to cancel classes.

Atlanta Public Schools was the first school system to call off classes. DeKalb County Schools followed suit a few minutes later, canceling Tuesday classes. Fulton, Cobb and Clayton County school officials canceled classes for Tuesday and Wednesday. Forsyth County, Marietta, Paulding County and Douglas County officials also announced Tuesday closures.

Public transportation gears up

While Hartsfield-Jackson International Airport officials said the airport would remain "open and fully operational this week," Delta Air Lines is waiving certain change fees for travelers scheduled to fly Tuesday through Thursday from or through Atlanta and other southeastern airports.

MARTA plans to run a normal weekday schedule Tuesday for its buses and trains, a spokesman said Monday night.

“We’re an essential provider of transportation services and we know that people are depending on us,” GM and CEO Keith T. Parker said in an emailed statement. “We’ve been making plans to prepare for bad weather and we’ll be running as much of our service as possible for as long as we can do so safely.”

Winter storm warning for far northern suburbs

Just after 4 a.m. Monday, the National Weather Service issued a winter storm warning for the far northern suburbs northward, effective from 7 p.m. Monday through 7 p.m. Tuesday.

The warning, posted for Cherokee, Forsyth, Hall, Banks, Jackson, Murray, Fannin, Gilmer, Union, Towns, Pickens, Dawson, Lumpkin and White counties, is calling for snow accumulations of 1 to 3 inches.

Late Monday morning, Deal declared a state of emergency in those 14 counties. The state of emergency was later expanded to also include Dade, Walker, Catoosa, Whitfield, Chattooga, Gordon, Floyd, Bartow, Polk, Paulding, Cobb, Fulton, Gwinnett, Barrow, Haralson, Carroll, Douglas, DeKalb, Clarke, Oconee, Oglethorpe, Wilkes, Walton, Rabun, Habersham, Stephens, Franklin, Hart, Madison, Elbert and Lincoln counties.

— Staff writers Mike Morris, Greg Bluestein, Kelly Yamanouchi and Marcus K. Garner contributed to this article.