Abnormal October heat in Midwest to fade by midweek as severe weather takes the reins

As the first week of October continues, residents across much of the North Central states and Great Lakes region will continue to experience an unseasonable warm spell with temperatures ranging between the mid-80s to lower 90s F. AccuWeather meteorologists say that although the peak temperatures of the week have already occurred in most Midwest locations over the weekend, conditions will remain toasty into Wednesday for a number of cities.

Temperatures soared between 15 and 35 degrees Fahrenheit above historical averages across the nation's heartland by the end of the weekend, setting new October record high temperatures. In Minneapolis, the daytime temperature soared to a record-breaking value of 92 F on Sunday, Oct. 1.

Typically, temperatures recorded on this date are in the middle to upper 60s F. Another hot spot across the Midwest was Fargo, North Dakota, where a max temperature of 96 F was observed on Sunday, setting a new daily record. On average, early October temperatures for Fargo are around 65 F.

Overnight temperatures remained high across the region on Sunday as the amplified pattern persevered. Numerous locations in South Dakota, such as Aberdeen, Sisseton, Mobridge, and Pierre, set record-high overnight temperatures on Sunday, surpassing the old records by several degrees in some cases.

Early this week, the overall pattern will be a classic setup for guiding the warmer conditions into the Midwest. An amplified northward surge in the jet stream has been pulling warm air across the Southern states northward into the Plains and Great Lakes. High pressure set up underneath this amplified pattern has also helped to promote generally dry weather across parts of the Midwest over the last day or so.

Those planning to participate in outdoor events and activities have already felt the impacts of the unseasonable heat and humidity early this week.

Events such as the annual Twin Cities Marathon slated to take place in the Minneapolis-Saint Paul area over the past weekend were canceled due to the dangerous heat, affecting roughly 8,000 marathon participants, 12,000 runners in the Twin Cities 10-mile race and thousands of other spectators.


Throughout the history of this marathon, dating back 42 years, it has never been canceled before due to the weather.

AccuWeather meteorologists recommend that any residents participating in outdoor activities, taking care of autumn yard work and even seasonal decorating should stay hydrated and regularly apply sunscreen while outside, given the lingering warmth and sunshine.

Widespread highs in the 80s are in store on Wednesday, including in Chicago, Detroit, Indianapolis, Cincinnati and St. Louis, which is still well above the historical average but slightly lower than the start of the week.

Much more pronounced cooling will spread from west to east Tuesday night and Wednesday as drenching showers and locally severe thunderstorms will mark the approach of a strong front from Canada.

Strong to severe thunderstorms began to develop across far southeastern Montana, eastern Wyoming, North Dakota, western South Dakota and western Nebraska Monday afternoon, with reports of hail and gusty winds. Throughout the overnight hours, steady rainfall spread across areas of the Dakotas as storms rolled eastward.

As the storm slowly pressed eastward through Tuesday night, the corridor for the strongest thunderstorms shifted to parts of South Dakota, southern Minnesota, Nebraska and western Iowa on southward to Texas. There were numerous reports of hail and damaging winds, especially in Nebraska, Kansas and Texas.

By Wednesday, the main storm feature will push into the Great Lakes region, and the threat of severe thunderstorms across the Midwest will gradually decline. However, intermittent showers and localized thunderstorms can still spread from Minnesota to Illinois and parts of Michigan.

Residents will observe a dramatic drop in temperature by the second half of the week as the cold front plunges into the region. Locations such as Saint Paul, Minnesota, that observed daytime highs in the 90s F on Sunday are forecast to have highs in the lower 50s F by Friday and Saturday. Similarly, residents in Chicago will observe a temperature drop on the order of 20-30 degrees throughout the week.

Looking ahead, forecasters say that the atmospheric pattern across the northern Plains late this weekend into the next week could present another setup that can usher in warmer conditions, although the next warm spell is not expected to be of the same intensity as early this week.

Want next-level safety, ad-free? Unlock advanced, hyperlocal severe weather alerts when you subscribe to Premium+ on the AccuWeather app. AccuWeather Alerts are prompted by our expert meteorologists who monitor and analyze dangerous weather risks 24/7 to keep you and your family safer.