WASHINGTON - A quick-moving clipper delivered a blast of snow in the D.C. region on Friday morning, causing complications on the roadways during the morning rush.
"This is a clipper," says ABC7 meteorologist Brian van de Graaff. "It moves really quickly, comes on heavy really quick and then it's outta here."
The National Weather Service posted a Winter Weather Advisory for D.C. and the surrounding suburbs until 10 a.m.
The snow began falling before 6 a.m. in some regions, and by 7:30 a.m. was moving out of the region heading north, hitting Prince George's and Anne Arundel counties in Maryland last.
Most of the major roadways were treated in advance of the quick winter system and while traffic moved slow, the cold temperatures and precipitation did not cause serious ice.
However, callers reported a "mess" on the length of the Dulles Toll Road, where reports of cars spinning out, freezing conditions and slush led many to believe the road had not been adequately treated.
On the George Washington Parkway, a major wreck around 7 a.m. on the northbound side before 123 caused traffic to be diverted and lanes to be closed. As of 9:30 a.m., the left lane was still blocked.
Callers also reported many side roads in the region were "skating rinks", very slick and precarious.
In total, Van de Graaff says accumulation would be just shy of an inch to a half inch in most areas.
Carroll County Public Schools are closed on Friday due to the weather.
A couple of school systems have delayed their openings. Check WTOP's Closings and Delays page.
Any snow is expected to end by lunch. Highs will be in the mid- to upper 30s Friday. Overnight lows could drop to 15.
Saturday brings a high of 40 and sunshine. Light snow possible late in the day and into Sunday. Sunday's highs will be around 40.
Maryland had already treated more than half of its major roads, including highways, as of Thursday afternoon, according to Charlie Gischlar with the Maryland State Highway Administration.
SHA tracks the storm through an in-house program and by consulting with the National Weather Service.
"We wanted to get this pre-treatment down so that it's highly effective in case it hits during the Friday morning rush hour. Basically, we want to get that first defense down that helps to stop that initial bonding of snow and ice to the pavement," Gischlar says.
While the state is doing its part to make the morning commute a safe one, Gischlar says this year he's noticed a change in drivers' patterns.
"All across the state this whole year, we've seen people get complacent. It's winter. It's cold. Anything that comes down has a chance of freezing. That's why we're out ahead of it, but we need drivers to play their part," he says.
He suggests drivers leave a half-hour earlier, so they don't feel the pressure to speed or make bad decisions behind the wheel.
D.C. crews will focus on treating major roads and elevated surfaces, if needed, according to John Lisle with the D.C. Department of Transportation.
"They'll be ready to apply salt if they need to. We're going to have about 80 trucks on the road," Lisle says.
Trucks have been pre-treated the roads with a brine solution.
"They can do that up to 48 hours before a storm. It dries on the roadway. That helps melt it until we can get salt down," Lisle says.
In Virginia, 350 trucks hit the roads at midnight to pre-treat before the snow. They were covering main thoroughfares in Fairfax, Loudoun and Prince William counties, according to Virginia Department of Transportation spokesperson Joan Morris.
Problem spots on major roads like the Fairfax County Parkway and routes 1, 7, 28, 29, 50 and 123 are pre-treated with salt brine, according to a VDOT news release.
On interstates 66, 95, 395 and 495 -- including bridges and ramps prone to freezing, such as the Springfield Interchange, I-66 at Route 29 and the Capital Beltway interchange at Route 1 -- crews use liquid magnesium chloride.
Flooding is still a concern, especially in Loudoun County, which saw significant rainfall Wednesday evening. Most of the affected roads are gravel and will not freeze, Morris says.
"Crews are going to be working this weekend in Loudoun (County). We have 20 people working on the gravel roads to restore them. At its height, we had over 54 roads closed in Loudoun," Morris says.
As of Friday morning, VDOT showed multiple water-related closures still in effect. See a list of roads closed in Virginia here.
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