A large storm system will develop overnight and spread waves of rainfall from the southern Plains and Tennessee Valley into the Ohio Valley and northeastern United States. On the back side of the storm system, we’ll see snow, heavy at times in the Dakotas over to Minnesota. Temps will plummet behind the cold front as arctic air quickly moves in from the northwest. This colder air looks to take up residence in the Great Lakes as we head through the middle part of the week.