Temperatures

Temperatures were slightly above normal to the south east and below normal for much of the Upper Midwest (Figure 1). Parts of northern Minnesota were 5-7°F below normal for the period, while areas of Kentucky were as much as 5°F above normal for the period.

Regarding minimum temperatures, I-80 was the dividing line between above and below normal temperatures (Figure 2). Minimum temperatures were generally near normal along I-80. Southern areas of the region were generally 3-6°F above normal for the week. The Upper Midwest was generally 2-4°F below normal for the week, with parts of northern Minnesota up to 6°F below normal for the week. As of July 21, Louisville, Kentucky, has seen 35 days of minimum temperatures above 70°F, making it the longest stretch of 70°F+ minimum temperatures in the city’s history.

Maximum temperatures were below normal for much of the region (Figure 3). In Illinois, Indiana, and Ohio, maximum temperatures were 1-3°F below normal, while in the Upper Midwest, some spots were close to 10°F below normal. In Eau Claire, Wisconsin, a maximum temperature of 70°F was observed on July 16, which was the coolest maximum temperature in July since 2017.

July 15-19 Heavy Rains & Drought

Precipitation was most plentiful in a belt stretching from southern Minnesota and Iowa south and east through Illinois, southern Indiana, Kentucky, and southern Ohio (Figure 4). In southern Indiana, some areas picked up over 400 percent of normal precipitation for the week. Evansville, Indiana, observed 2.16 inches of precipitation on July 19, making July 19 the wettest July day since 2018. Evansville also observed the wettest three-day period in July on record, with 5.15 inches of precipitation observed July 17-19. The same storm system that brought heavy rains to Kentucky also brought heavy rains to the Upper Midwest; Ashland and Bayfield counties in northern Wisconsin recorded 2-4 inches of rain over 24 hours, which caused area waterways to rise to near record levels. At the Ashland Exp (Experiment) Farm in Bayfield County, a station with records dating back to 1893 observed 2.97 inches of rain on July 16, which was the wettest July day since 2020 and tied for the 5th wettest July day on record.

Dry conditions continued to improve across the Midwest thanks to precipitation through the week. By week’s end, D0 (abnormally dry) decreased by 8 percent across the region (Figure 5). Most of the improvement came from Missouri, where D0 was completely eliminated from the state for the first time since June 2022. Slight decreases were also observed in the D1 (moderate drought) and D2 (severe drought) categories.

Severe Weather

There were several rounds of severe weather this week, and the vast majority of storm reports were wind reports. Most of the tornado reports occurred on July 16, when 10 tornado reports were made, mainly in Wisconsin. There were five confirmed tornadoes across Wisconsin on July 16, the strongest of which was an EF1 with estimated peak winds of 95 mph that spent 7 miles on the ground in Dodgeville. An EF0 tornado tracked 5.6 miles through northwestern Dane County, not far from Madison, with estimated peak winds of 80 mph.