Warm Temperatures

Unseasonably warm temperatures continued into the second week of October across the Midwest, with temperatures 2-13°F above normal (Figure 1). The greatest warmth was in the eastern Midwest where most locations in Michigan and Ohio saw average temperatures 9-13°F above normal. While both maximum temperatures (Figure 2) and minimum temperatures (Figure 3) were above normal region-wide, it was once again the minimum temperatures that were most extreme. Widespread areas east of the Mississippi River measured minimum temperatures 9-16°F above normal.

Late First Freeze

Ongoing warmth has resulted in a delay of the first fall 32°F freeze, especially in the northern portion of the Midwest where the historical median first freeze date ranges from September 21 – October 10 (Figure 4). As of October 17, freeze conditions were nearly absent region-wide except for isolated locations in Minnesota, Wisconsin, and northern Michigan (Figure 5).

Ample Rain in Central Midwest

A wide area of 1-3 inches of precipitation fell across the central Midwest including Missouri, southern Iowa, Illinois, Indiana, northwest Ohio, and Michigan (Figure 6). Less than 0.25 inches of precipitation fell along the Minnesota-Wisconsin border.

An Active Week of Severe Weather

Several low-pressure systems tracked across the Midwest this week bringing severe weather to the region, including 28 tornado reports. Eleven tornadoes were reported in Illinois on October 11, six in Minnesota on October 13, one on October 14 in Michigan, and 11 occurred on October 15 in Indiana and Ohio with one associated injury reported in Ohio. The October 11th (Figure 7) and October 15th (Figure 8) events also resulted in a combined 56 wind reports, with damage to large trees and residential structures throughout Illinois, Indiana, and Ohio.