While the Eastern Seaboard of the United States will stay mostly clear of wet weather on Tuesday, Kari Strenfel of the site Weather Underground said the outlook isn't as promising for the rest of the nation on election day.
A low-pressure system will move northeastward over south central Canada. A cold frontal boundary associated with this system will extend south southwestward over the western Great Lakes, the upper Midwest, the middle Mississippi Valley and the southern Plains. As moisture from the Gulf of Mexico collides with this frontal boundary, heavy rain and thunderstorms will develop over the southern Plains, the western Gulf Coast and the lower Mississippi Valley.
Lighter rain will spread across the northern Plains, the upper Midwest, the Tennessee Valley and the Ohio Valley, while mixed precipitation will be possible across northeast Minnesota and northern Wisconsin.