Freezing drizzle across the area created some problems for commuters during their morning drives in to work.
The biggest problems were on the secondary roads, not the main roads. Anything that was pretreated was fine, but roads that weren't became very slick, very fast.
The reason? Some very light precipitation that started falling overnight, according to NBC Washington meteorologist Tom Kierein.
But Tuesday morning's freezing drizzle won't be the end of our worries.
Another round is expected, and the National Weather Service has issued a freezing rain advisory from 9 p.m. Tuesday until 11 a.m. Wednesday for the entire D.C. area.
On Wednesday, for the second day in a row, federal agencies in D.C. will be open, but federal workers will have the option to telecommute or take unscheduled leave. Emergency employees are expected to show for work as scheduled Wednesday unless otherwise directed.
An enormous area of the country will be affected by a deepening area of low pressure moving out of the southern Plains into the Chicago and Detroit area later today. There is quite a bit of warm air to the south of it, but to the north it is very cold, and that contrast is creating a very powerful area of low pressure, turning that into a major blizzard with heavy snow and strong winds, and there could be significant icing across parts of Indiana, across Ohio and into Pennsylvania. That storm will then head east into New England, leaving behind a combination of deep snow, strong winds, ice, heavy rain and maybe even some severe storms that could produce tornadoes.
This storm could impact parts of the country throughout the day today, tonight and into Wednesday and early Thursday. Hundreds of flights are canceled or delayed as a result of this storm. There could be widespread power outages affecting millions of people at the height of the storm.
Thankfully, those of us in the Washington region will not be feeling the heavy effects of the storm, with just a little bit of icing this morning causing many school systems to delay or close as a sheet of ice formed on untreated surfaces due to the patchy, freezing drizzle, which ended by noon as temperatures climbed above freezing.
After sunset, we will likely have rain sweep through the region, and after midnight we may have the temperatures drop below freezing again. Periods of freezing rain could then cause ice to accumulate, mainly on elevated surfaces like tree limbs and power lines.
By dawn Wednesday, there could be a tenth to a quarter inch of ice on tree limbs and power lines, which may cause some scattered power outages.
During the day Wednesday, temperatures will get above freezing by late morning. Rain will continue and eventually end by mid- to late afternoon as temperatures get into the 40s. This rain, combined with snow melt, may cause localized flooding.
We then get back below freezing Wednesday night into Thursday morning. So what remained liquid overnight will freeze up Thursday morning.
After cold weather Thursday and Friday, there may be some snow Saturday, Kierein said.
Power was finally restored Monday to those Pepco customers still in the dark from last week's storm, but utility companies are bracing for another round of outages with this storm.
The National Weather Service has issued a winter weather advisory for most of the D.C. area until noon Tuesday.
The NWS issued a winter storm watch for the following areas from late Monday night through Wednesday morning:
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