Around 47 million Americans were under a severe weather watch Wednesday as a winter storm threatened to pelt Kentucky, the Ohio Valley and southern Plains with ice and record-setting snow before moving towards New York City and Washington, D.C.
Heavy rain was forecast to freeze as the what is expected to be the last major system of the winter moved towards the East Coast after pounding the Rockies and northern Texas on Tuesday.
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In Kentucky, rain heavy enough to cause flooding was expected to turn into snowfall of up to 10 inches late Wednesday — five times the average March snow for Louisville and just short of the all-time March record of 12 inches.
"The snow and ice covers a huge area, from the Ohio Valley all the way down into northern Texas and the southern Plains and then on Wednesday night into Oklahoma City, northwestern Virginia and southwestern Pennsylvania," Weather Channel lead forecaster Kevin Roth said.
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The snow will then hit New York City — which could see up to five inches — Philadelphia and Washington, D.C., on Thursday, disrupting both the morning and evening commutes.
There was yet more snow in New England on Tuesday night, but it wasn't quite enough to set an all-time record in Boston, which remains 1.9 inches away from its snowiest ever winter. More flurries are forecast in the coming days, but the city has until June to set a new record.
Despite the widespread winter storm, forecasters say warmer weather is around the corner. "This looks to be is the last of the major weather patterns this winter," Roth added.