This week, a swath from the Midwest to the Northeast will face a significant risk of severe weather. Thunderstorms will rumble across these regions on Monday and Tuesday before becoming more confined to the East by Wednesday. In the wake of the storms, much cooler and less humid air will move into the Midwest, Great Lakes, and Northeast, while the responsible cold front will stall in the Southeast late this week.
Thunderstorms Begin in the Midwest
At the start of the weekend, a concentrated area of thunderstorms from western and central South Dakota caused widespread wind damage. A second area of numerous wind reports stretched from Minnesota into western Wisconsin. AccuWeather meteorologists accurately forecasted another round of storms for parts of the Midwest, despite areas like Montana and western South Dakota being west of the severe zone on Sunday.
A line of thunderstorms developed in southeastern Minnesota, moving southeastward through Chicago, central Illinois, and Indiana, bringing flash flooding and damaging winds.
Midwest Risk Continues into Monday
The cold front, which is a focus for showers and thunderstorms, will continue to move southeast on Monday. Minnesota and Wisconsin will experience a third day of storms, but these should be restricted to the morning in northwestern and central Minnesota.
“Minneapolis will likely have their severe storms for the Monday morning commute,” mentioned Roys, AccuWeather Meteorologist.
Farther east, thunderstorms will develop during the afternoon and may not weaken after sunset. “The storms in Milwaukee and Chicago will be closer to the evening commute, and much of Michigan and Indiana, including Detroit and Indianapolis, will have their highest risk of severe thunderstorms during the overnight hours,” explained Roys.
Like the storms on Sunday, the thunderstorms at the start of the workweek will be capable of all severe hazards, including destructive winds, hail, flash flooding, and isolated tornadoes.
Thunderstorms in the Northeast
In the Northeast, only a few spotty thunderstorms developed over the weekend. However, AccuWeather meteorologists are concerned about a more widespread risk of severe weather on Monday. “Across the Northeast, thunderstorms will have plenty of heat and humidity to work with, along with energy that may be left over from the storms that affect the Ohio Valley on Sunday,” explained Roys.
While the chance for hail and tornadoes is negligible in the Northeast, damaging winds and downpours are the main hazards. Coastal cities might largely be spared from severe weather, but “the cities on the I-95 corridor could have thunderstorms, with the suburbs to their north and west more likely to face potentially severe thunderstorms,” noted Roys.
Tuesday and Wednesday Outlook
Cooler and drier air will arrive in the wake of the cold front on Tuesday, ending the threat of thunderstorms in Minnesota and Wisconsin. However, the severe thunderstorm risk will continue farther south and east due to the hot and humid air and the advancing cold front. “The strongest storms will be from central Illinois to northwestern Ohio, capable of producing flooding downpours, damaging wind gusts, and hail,” outlined Roys. Outside of that zone, there will still be some risk of severe weather.
By Wednesday, the Midwest will catch a break as the cold front moves to the East Coast. “The cold front moving into a very hot and muggy air mass in the northern Tennessee Valley and into the Northeast and mid-Atlantic will lead to explosive thunderstorm development,” explained Roys. AccuWeather experts highlight a zone from far southern Maine to northern Maryland for the highest potential for severe weather at midweek. Cities from Washington, D.C. to Boston are likely to have storms during the afternoon commute or early evening hours, snarling travel for those driving home.
In the wake of the front, widespread lower humidity and temperatures below the historical average will grace the Midwest, Great Lakes, and interior Northeast from Wednesday into Thursday. The degree of air mass change along the East Coast will depend on how far the front advances. Cooler and less humid air should arrive by Thursday night and Friday.
Late Week Developments
As is typical in the summer, the cold front will eventually slow down and stall as it moves into the Southeast, setting up a zone of potential downpours. This could cause instances of flooding, but much of the region is also in a drought, so the rain will largely be beneficial in the grand scheme of things.
