Flood watches are in effect across the Northeast, as far south as Delaware. Two to four inches of rain could flood roads. The Weather Channel's Kelly Cass reports.
Heavy rains and snow will pound the eastern United States into Monday, possibly leading to downed trees, power outages and flight delays as a low pressure system from the Gulf of Mexico moves through the region.
Intense precipitation from the Nor'easter storm started Sunday morning, with two to four inches of downpour expected along the Mid-Atlantic Coast, which will make for soggy conditions in New York, Philadelphia and Washington, D.C.
As for snow, "the areas of concern are western New York, western Pennsylvania, extreme eastern Ohio, parts of northern West Virginia and extreme western Maryland," weather.com reported. Buffalo and Pittsburgh could see six inches or so, while more than a foot is possible in higher elevations.
"It's going to a very, very intense Nor'easter," said Michael Eckert, senior branch forecaster with the National Weather Service based in Camp Springs, Md.
"Snowfall rates may exceed 1" per hour Sunday night into early Monday, accompanied by thunder and lightning," weather.com added.
"The weather will be going downhill during the day on Sunday," Eckert said.
On Sunday night, the inland side of the weather system will see an influx of cold air, as falling rain morphs into heavy snow that will blanket western parts of New York state and Pennsylvania, as well as West Virginia, he said.
Heavy snow could lead to downed branches and even trees. As a result, forecasters expect broken power lines and widespread outages in some areas.
With the storm came a spate of disruptions. Pro baseball games were postponed in New York and Washington. The space shuttle Enterprise's scheduled arrival in New York City was pushed back. An Earth Day celebration at a park in Virginia Beach, Va., was canceled.
This weather pattern would produce a blizzard if it had come in January, but because the spring air is warmer the storm is not expected to be as severe, Eckert said.
Nevertheless, airports in New York, Boston and Philadelphia could see flight delays on Monday due to the storm, said Eckert.
On Saturday, Minnesota had a few small tornadoes that struck in the western half of the state, the National Weather Service said. They caused no injuries but damaged barns near the town of Milan and to a flower shop in Lucan, said Weather Service meteorologist Bryon Paulson.
"We had everything, rain, nickel-sized hail, small tornadoes and snow," he said.
The town of Chisholm in northeast Minnesota received nearly 6 inches of snow, after getting a foot a week ago. That followed a mild winter with little snow, he said.
Reuters and The Associated Press contributed to this report.
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