More than 90 million people from the Plains and Midwest to the Mid-Atlantic and Northeast are under some sort of winter weather watch, warning or advisory. Nearly 20 million are facing a flood warning, watch or a flash flood watch across the Southeast.
• Winter weather advisories are out for Oklahoma City; Wichita, Kansas; the Kansas City area, St. Louis; Chicago; Milwaukee; Indianapolis; Louisville, Kentucky; Cincinnati and Columbus, Ohio; and Pittsburgh, where light to moderate, snow or ice is forecast.
• There are winter storm warnings for Omaha, Nebraska; Des Moines, Iowa; and Minneapolis, where up to 9 inches is expected to fall.
Washington and Baltimore to take the storm’s brunt
• Snow and ice will cause problems for the Baltimore and Washington areas. Four to 6 inches of snow and sleet are expected in both cities, with wintery weather starting overnight and lasting into Thursday. As warmer air mixes in, ice accumulations of a 10th of an inch are possible.
• Winter storm watches with heavy snow or ice are expected from Philadelphia northward to west of New York City. Some to 2 to 3 inches of snow could fall. New York will likely see snow Wednesday afternoon before it transitions to rain by the evening.
• If you are a student in the School District of Philadelphia — the nation’s eighth largest by enrollment — you can stay home Wednesday. If you work in an administrative role, the decision whether to open offices will be made by 5 a.m. Wednesday. If you are a building engineer, the district says to come to work.
Flooding to affect much of South, especially Tennessee
• Two to 4 inches of rain is expected across the region, with even higher amounts of 5 to 7 inches in Memphis and Nashville through the end of the week.
• Multiple rounds of rain will affect North Georgia this week. Cities such as Atlanta are likely to receive 2 to 3 inches of rain, and even higher amounts are expected in the mountains to the north.
CNN’s Dave Hennen and Chuck Johnston contributed to this report.