Sledders took advantage of Monday's snowfall on the hills at the Community College of Baltimore County in Catonsville. (Barbara Haddock Taylor/Baltimore Sun video)

Monday's snowfall introduced a spell of more dangerous cold that could continue to disrupt work, school and travel in the region for several days.

Temperatures early Tuesday morning were forecast to threaten a record dating to 1873, with lows in the single digits — possibly tying or breaking a record for Baltimore's coldest March day. It was expected to become only the sixth time single-digit temperatures have been recorded here in March.

Already Monday evening, Anne Arundel County schools had canceled classes Tuesday and Baltimore City and Baltimore, Carroll, Harford and Howard counties planned to start two hours late.

The frigid polar air could challenge storm cleanup efforts, with little snow melting expected until Wednesday or Thursday. The blanket of snow caused fender-benders, grounded flights and closed governments, offices and schools across the region.

Many folks, including letter carrier Ray Russell, who traversed South Baltimore's Riverside neighborhood Monday in the snow, were more than ready for spring.

"I think we all are," said Russell, wearing a zip-up sweatshirt over his blue button-down uniform shirt, snow pants, thick boots and a wool cap. "I'm ready to start complaining it's too hot."

The storm brought snow, freezing rain and near-record cold from the Mississippi Valley and Great Plains to the Mid-Atlantic, as a strong front of Arctic air moved in from the north and Gulf of Mexico, moisture rose from the South. The storm was blamed for at least four weather-related traffic deaths in Texas, Oklahoma and Tennessee over the weekend.

Snow accumulation across the Baltimore region was less than the forecast of 6 to 10 inches. Tricky dynamics between the storm's two elements made snowfall predictions a challenge. Over the weekend, it appeared the cold air would move in place ahead of the Gulf moisture, but when they reached Maryland on Sunday night, atmospheric temperatures weren't immediately cold enough for snow, said Jim Lee, meteorologist in charge of the National Weather Service's Baltimore/Washington forecast office in Sterling, Va.

That allowed for a mix of rain and sleet in many areas into early Monday morning, he said.

The region's snowfall totals included 6 inches in Phoenix, 5.1 inches in Bel Air, 5 inches in Owings Mills and Edgewater, and 4 inches in Hamilton and Woodstock, according to the weather service. As of 1 p.m., 3.8 inches had fallen at Baltimore-Washington International Thurgood Marshall Airport, making this the snowiest March there since 2009.

As the snow ended, the freeze intensified. Temperatures dropped to 16 degrees by 10 a.m. Monday at BWI and hovered in the upper teens the rest of the afternoon.

Overnight lows were expected to drop to around 5 degrees at the airport, Lee said. The last time single digits were recorded in Baltimore in March was March 4, 2009, with a reading of 8 degrees. The record for Tuesday's date and for the entire month of March in Baltimore is 5 degrees, set in 1873.

If winter won't leave, some were eager to escape it instead, but the snow foiled those plans. The Olivera family from Claymont, Del., spent Monday stuck at BWI, trying to make their way to Florida for a much-anticipated cruise to Key West and Cozumel.

Parents Malinda and Othello, 10-year-old daughter Sa'rah, 6-year-old son Othello and grandmother Linda Lewis left early in the morning for a treacherous 21/2-hour drive to the airport, only to find their flight to Miami had been canceled. They rebooked for a flight late in the day and hoped to join the cruise in Key West on Tuesday.

"I just can't wait until this winter is over. I'm looking forward to sun," said Othello Olivera, a pharmacy technician.

The airport had 200 employees working 75 pieces of equipment to plow, pile and melt snow from the runways and taxiways, said airport spokesman Jonathan Dean, but dozens of flights were canceled nonetheless. Half of flights slated to depart from BWI and more than a third of arrivals were canceled as of Monday afternoon, according to FlightAware.com. Dozens of other flights were delayed.

In the Baltimore region, the snow forecast was enough to cancel schools, with most announcements made Sunday night. The federal government closed its offices, and attractions including the National Aquarium and Maryland Zoo also closed. The Baltimore City Council canceled its meeting scheduled for Monday night.

"Everyone in Maryland is a little snow-weary at this point," said Anne Arundel County Executive Laura Neuman. "But we're focused as if this was the first storm of the season."

Neuman said she sent out an email over the weekend: "I said, I know it's March and everyone's ready for spring, but this could be the worst storm of the season."

The Maryland State Highway Administration said it and the Maryland Transportation Authority had a combined 2,600 pieces of equipment on the roads salting and plowing, and urged Maryland residents to stay off the roads if possible.

Baltimore transportation director William Johnson said rainfall Sunday night prevented crews from salting roads because it would have been washed away. But by midday, city crews had cleared major roadways, he said.

Despite warnings that the combination of ice, snow and winds could cause widespread outages, Baltimore Gas and Electric Co. reported few problems.

After the snow, attention turned to the low temperatures ahead. Highs Tuesday are expected in the upper 20s, with brief periods rising above freezing into the mid-30s Wednesday and Thursday, and highs in the 40s by Friday.

Baltimore City officials issued a "Code Blue" alert opening up extra space in shelters and sending staff out to visit the homeless to encourage them to seek shelter.

City fire officials said they were confident they would be able to respond to any emergencies despite previous bouts of intense cold causing some fire hydrants to freeze up and become unusable.

Typically, the Baltimore region does not get cold enough for frozen hydrants to be an issue, and hydrants in the area use a design known as "dry barrel," meaning there is not supposed to be any water inside the above-ground part of the hydrant to guard against freezing. But if one does not drain properly or ice forms on the outside, that can lead to problems.

"A single drop of water can seal something shut," said Ian Brennan, a spokesman for the Baltimore City Fire Department.

Crews battling blazes in Locust Point and Roland Park in January had to contend with some frozen hydrants, but there are simple work-arounds, according to Brennan, like running a hose to the next hydrant on the street. Fire engines carry enough water to get started tackling a fire, giving crews time to get hooked into the hydrants.

Fire officials in Anne Arundel and Harford counties said extra efforts must be made to provide firefighters a place to warm up while working in cold conditions.

Meteorologists foresee a return to normal temperatures, with highs around 50, by the weekend. But before that, the region has to endure at least a couple more remarkably frigid nights, said Andy Mussoline, a meteorologist with AccuWeather.com.

"In terms of Arctic air, this is extremely impressive for early March standards," Mussoline said. Monday night into Tuesday morning "actually looks like our coldest night perhaps until next winter. This may be the bottom here for us."

Reuters and Baltimore Sun reporters Ian Duncan, Jessica Anderson, Pamela Wood and Alison Knezevich contributed to this article.

sdance@baltsun.com

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