President's Day has produced some notorious East Coast snowstorms in the past, but on Monday the East will have a pleasant day as mild temperatures kick off the week. The Upper Great Lakes, however, are expected to get heavy snow.
The National Weather Service issued winter weather advisories covering 6 million people in parts of Minnesota, Iowa, Michigan and upstate New York. Snow will move into the Upper Great Lakes throughout Monday, and by Tuesday morning, the snow will be over parts of the Lower Great Lakes and the Northeast.
There could be a few areas of mixed precipitation over parts of the Northeast overnight Tuesday, but the Interstate 95 corridor is expected to predominantly experience rain. Snowfall totals will be 2 to 6 inches from the Great Lakes to New England, with locally higher amounts up to 8 inches possible.
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Light snow over Chicago could cause some travel delays Monday, while the East Coast rainstorm Tuesday will likely cause some delays at big hubs like Atlanta, Washington, New York and Boston.
On the southern side of the system, rain will drop on parts of the Ohio River Valley, moving southward to the Lower Mississippi Valley and the Gulf Coast by Monday evening. The area has been hit by river flooding, with 158 gauges above flood stage and 10 million people under flood warnings.
The Pearl River at Jackson, Mississippi, is at major flood stage, and it was expected to crest Monday at 37.5 feet, which would be its third-highest crest in 100 years.
On Tuesday, the rain will move into parts of the Great Lakes and the Ohio Valley and into the Southeast and the Northeast. Rain will continue through Wednesday over the Southeast, where 1 to 2 inches will fall over saturated areas.
Meanwhile, the 5- to 15-degrees-above-average temperatures east of the Rockies will begin to drop Tuesday. High temperatures will plummet to 5 to 15 degrees below average first across the Plains on Tuesday, then in the Midwest on Wednesday and eventually along the entire East Coast by Thursday.