Though occasional flurries fell in Baltimore throughout the afternoon and evening, the city was spared the predicted snow accumulation that brought out the salt trucks and sent people home early from work and school.

What happened to the winter weather forecast for Wednesday?

"There was a larger mass of warm air invecting inland than expected," said National Weather Service meteorologist Matthew Kramar, who is stationed in Sterling, Va.

That warm air coming off the ocean pushed the rain-snow line farther west, leaving Baltimore with a wintry mix that was mostly rain, he said. Winds blew more heavily from the east, and the region's dew points were higher as well, Kramar explained, also inhibiting snow from reaching the city.

Shortly before the afternoon rush hour began Wednesday, the weather service canceled its winter weather advisory for Baltimore and southern Baltimore County, and reduced the amount of expected snow accumulation, which includes any snow melt, to less than one inch.

On Tuesday, state highway crews pre-treated major routes. And as the snow front made its way east early Wednesday afternoon, salt trucks were again on the roads, said Kellie Boulware, spokeswoman for the State Highway Administration.

But the only white powder to grace most of the Baltimore Beltway Wednesday was rock salt that migrated to the medians by late afternoon.

Area school systems, including Baltimore, Carroll, Harford and Howard counties, canceled afternoon and evening activities. See more closings here. D.C.-area federal offices remained open, but employees concerned about the evening commute were allowed to take unscheduled leave.

The weather service's winter weather advisory was scheduled to last until 10 p.m. for areas north and west of Baltimore, but was lifted more than an hour before. Some areas in the central part of the state along the Maryland-Pennsylvania border were reporting up to 1.5 inches of snow by that time, but the accumulation elsewhere was substantially below that amount.

A winter weather advisory for snow means that periods of snow will cause travel difficulties by creating snow-covered roads and sidewalks and limiting visibility. The greatest impact is hazardous travel due to low visibility and snow-covered roads, especially untreated secondary roads.

Thursday is expected to be sunny, with a high near 48 and west winds between 9 and 11 miles per hour. Thursday night should be mostly clear, with a low around 30 and west winds between 5 and 7 miles per hour.

Friday's daytime weather is expected to be similar to Thursday. Snow may begin after 1 a.m. Friday night, which has a 20 percent chance of precipitation.

There is a 40 percent chance of precipitation, which could occur as rain or snow, on Saturday. Temperatures are predicted to be high 30s.

Whether Saturday's precipitation occurs as rain or snow will depend on which reaches Baltimore first, an Arctic air mass or the storm front, said Kramar.

steve.kilar@baltsun.com

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