Average- to Below-Average Temperatures Bring Relief from the Heat

Much of the Midwest had average- to below-average temperatures this past week (Figure 1). The exception was in eastern portions of Minnesota and Iowa, and southern portions of Missouri and Kentucky. Northern Michigan was the coolest region with average temperature departures ranging from 2-6°F below normal. Baraga County, for example, recorded an average temperature of 60.6°F (6°F below normal). Isolated areas in Missouri saw more extreme above-normal temperature departures. Maximum temperatures showed the largest departures this week. Below-normal maximum temperatures were observed in Illinois, Indiana, Michigan, Ohio, and Wisconsin resulting in a break from the heat (Figure 2). Above-normal maximum temperatures continued in Missouri. Howell County, Missouri recorded an average high temperature of 101°F. Yes, you read that right. The average temperature for the week was 85.9°F, which was 8.5°F above normal. This location’s single-day maximum temperature of 108°F tied the record set in 2011. Minimum temperature departures showed a similar pattern as the average temperature departures (Figure 3). This week, 39 daily high minimum temperatures records were set in Missouri (Figure 4). In the cooler states, there were 8 low minimum and 14 low maximum temperature records broken or tied this week (Figure 5).

Variable Rainfall with Isolated Pockets of Heavy Rain

Much of the Midwest had a relatively dry week with below-average rainfall in most areas. Many locations in the Midwest had precipitation departures of 0.5 to nearly 1.5 inches below normal (Figure 6). Some locations received less than 25% of normal rainfall (Figure 7). Southern portions of Missouri and Michigan saw the least rainfall during the week, with over 50 Missouri Stations receiving no rainfall. However, last week’s precipitation pattern has switched in the central Midwest, bringing heavy rainfall to portions of central Illinois, southern Indiana, and southern Kentucky. Many daily precipitation records were broken through this lower Midwest corridor (Figure 8), with a swath of 1.5 to 4-inch rainfall totals (Figure 9). Ohio County, Kentucky received 7.7 inches of rainfall (6.74 inches above normal), with 4.4 inches falling on July 9. Outside this region, there were only a few areas that received normal to above normal amounts of rainfall (primarily northern Wisconsin, and Michigan).

Severe Storm Reports

There were 2 tornado, 32 hail, 4 large hail, 117 wind, and 6 high wind reports this week (Figure 10).

July 8 - A brief and isolated tornado was observed in McDonough County, IL. There were many wind reports resulting in tree damage across the Missouri, Illinois, and Kentucky area. There were 3 hail reports, with the largest being a 1.5-inch report in Darmstadt County, IN.

July 10 - In Iowa, a single storm produced 5 high wind reports; Carroll County recorded the highest at 90 mph. Northern Minnesota received many wind and hail reports, with the largest hail reports. There were 9 hail reports of at least 1.5 inches, with one 2-inch report.

July 11 - An EF-0 tornado was confirmed on the shore of Lake Fenton, Michigan. There were multiple wind reports across Wisconsin, Illinois, and Michigan. Many of these reports were produced by the same storm that produced the tornado.

July 14 - Due to an isolated storm, 2-inch hail was reported near Lake Park, MN that resulted in property damage.

Intensifying Drought

The July 12 US Drought Monitor brought some improvement to the abnormally dry (D0) areas in southern Wisconsin, Illinois, Indiana, Ohio, and Kentucky. However, moderate drought (D1) was expanded in portions of Indiana, Kentucky, Missouri, and southeastern Minnesota (Figure 11). Severe drought (D2) was introduced in portions of central and southwestern Kentucky. The extreme drought (D3) in northwestern Iowa remained. Although many areas saw an increase in drought severity, the total land in D0-D3 area decreased by 7.66% from last week.