Baltimore County officials asked residents to keep vehicles off the street and in driveways, if possible, to allow snow plows to do their job, while in Howard County, officials planned to close Ellicott City's Main Street for snow removal.

Despite salt shortages in some parts of the country, local jurisdictions and state officials said they had plenty to treat roads, though many already spent more this season on plowing and treatment than budgeted.

Howard County has exceeded its $1.2 million budget for snowstorms this fiscal year, county spokesperson Mark Miller said. Before Sunday's snow, he said, the county had spent $2.4 million cumulatively on weather incidents — double what was budgeted — but had a $2 million natural-disaster contingency fund to fall back on.

Baltimore County officials also said they had sufficient salt, and Rawlings-Blake said the city's stores were at 85 percent of capacity.

The State Highway Administration has exceeded both its snow removal budget of $46 million and its normal annual spending of $70 million, spokeswoman Valerie Burnette Edgar said. The agency typically asks the General Assembly to make up the difference, though it has sought to gradually increase the budget each year, she said. The agency has used 319,000 tons of salt so far this winter and had about 250,000 tons on hand for use Wednesday and Thursday.

The storm snarled air traffic Wednesday, with a coating of ice and snow across the Southeast leading to more than 3,500 cancellations and 2,000 delays across the country, according to FlightAware.com. About 100 flights to and from Baltimore-Washington International Thurgood Marshall Airport were canceled Wednesday, with nearly 50 delayed.

More than 75 flights scheduled to and from BWI on Thursday were canceled Wednesday afternoon.

The storm forecast disrupted what was scheduled to be the election season's first forum of gubernatorial candidates in Maryland. Organizers canceled an event that had been scheduled for 7 p.m. Thursday at Israel Baptist Church in East Baltimore. Democratic candidates Lt. Gov. Anthony G. Brown, Attorney General Douglas F. Gansler and Del. Heather R. Mizeur and Republican candidate Charles Lollar had been expected to attend.

It remained to be seen how Thursday's snow will stack up against historic storms, but it comes at a time of year close to he anniversaries of many memorable snowfalls.

More than 21 inches of snow fell for three days starting Feb. 12, 1899, in what became known as the Valentine's Day Storm. Mail service and rail travel came to a standstill in what was the "worst blizzard ever known here," The Baltimore Sun reported at the time.

The National Guard was mobilized when 22.8 inches of snow fell Feb. 11, 1983, amid gale-force winds. That storm ranks as the second-highest single-day snowfall on record here.

The "Snowmageddon" of 2010 was capped off with a 15.5-inch snowfall on Feb. 10, for a total of nearly 45 inches of snow in six days.

Some melting of Thursday's snow is expected Friday, with highs forecast around 40 degrees and partly cloudy skies during the day before a chance of light snow in the evening. But then a cold weekend is ahead, with lows dropping back to the teens Saturday and possibly single digits Sunday, and highs in the mid-30s.

Baltimore Sun Media Group reporters Michael Dresser, Nayana Davis, Yvonne Wenger, Lauren Loricchio, Amanda Yeager and Pamela Wood and researcher Paul McCardell contributed to this article.

sdance@baltsun.com

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