Drenching thunderstorms will spread from the midwestern to the northeastern United States from late this weekend into early next week.
"Potent storms will push across the Upper Midwest [late] this weekend before working their way into the eastern Great Lakes and Northeast Monday and then into the mid-Atlantic on Tuesday," according to AccuWeather Senior Meteorologist Dan Pydynowski.
The storms will ride along the northern fringe of building triple-digit heat across the central U.S.
"With hot and humid conditions in place across the region, some of the storms could turn rather strong," Pydynowski explained.
Heavy downpours and locally damaging winds will be the primary threats, he said.
While storms will be most active during the late afternoon and evening, a few could remain quite feisty well into the overnight hours.
Stormy weather will start off across the Upper Midwest on Sunday.
Areas from Minneapolis to Cedar Rapids, Iowa; Chicago; and Green Bay, Wisconsin, may face one or more rounds of storms on Sunday and/or Sunday night.
As storms hit the Midwest on Sunday, warmth and sunshine will be the theme across the Northeast to end the weekend.
Residents from Washington, D.C., to Buffalo, New York, and Boston will not have to worry about their outdoor plans being cut short by wet weather on Sunday.
Wet weather will shift out of the Midwest and take aim at the eastern Great Lakes and interior portions of the Northeast on Monday.
Cities such as Indianapolis, Detroit, Cleveland, Pittsburgh and Syracuse, New York, could face a gusty thunderstorm or two to start the workweek.
Wet weather may hold off until Monday night and Tuesday along the northeastern I-95 corridor, Pydynowski said.
Incidents of flash and urban flooding are possible in the heaviest downpours during the Sunday to Tuesday time frame.
Areas that have been hit hard by heavy rain recently, such as Minnesota and West Virginia, only need 1.50 inches of rain or less in one hour to induce flash flooding.
Torrential downpours could cause delays in the air and on the road for a time.
Storms may become less frequent across the Midwest and Northeast for the second half of the week.