After drought was added a week prior, moderate to heavy rainfall led to minor relief in parts of Iowa, Illinois and Missouri during the week
(Figure 1). Amounts of more than an inch were common across Iowa, southern Illinois, southern Indiana, southern Missouri, northern Ohio and southern Minnesota. Higher amounts over three inches were also observed in central Iowa and southeastern Missouri. Many of these areas had two to three times the normal amount for the week (Figure 2). More than 90 daily precipitation records were broken across the region
(Figure 3). Meanwhile, very dry conditions were observed across Wisconsin and most of Michigan. Less than a quarter inch fell in northeastern Wisconsin, northern Lower Michigan and the eastern U.P. of Michigan.
Northwest to Southeast Temperature Divide
Temperatures were divided from northwest to southeast as cooler Canadian air began to move into the region as the week progressed (Figure 4). Most of Minnesota, Iowa and Wisconsin were 1-3°F below normal while Ohio and eastern Kentucky were 2-3°F above normal. Maximum temperatures were cooler across the western half of the region
(Figure 5), while minimum temperatures were divided with Missouri, Indiana, Ohio and Kentucky 2-4°F above normal, compared to 2-4°F below normal in the Upper Midwest (Figure 6). More than 30 daily high minimum temperature records were broken in the southern half of the region
Severe thunderstorms across the southern Midwest led to more than 370 storm reports, with more than 340 for thunderstorm winds (Figure 8). Most of this severe weather occurred from August 18-20. Two tornadoes were reported in Iowa on August 19 with damage to roofs and outbuildings. More than 200 wind reports were recorded on August 20 alone as a strong bowing line of thunderstorms moved from southeastern Iowa through central Illinois and southern Indiana
(Figure 9). Wind gusts of 55-60 mph were reported. An injury was reported near the Indianapolis Airport as a large tree fell on a car driving on a road.
Drought Introduced in Kentucky
While improvements were made in Iowa from rainfall, moderate drought was added to north-central Kentucky in the August 20 U.S. Drought Monitor (Figure 10). Abnormally dry conditions also more than doubled in Kentucky as well as agriculture was being affected and ponds were low. A drier week also increased abnormally dry conditions across Michigan, with more than half the state now considered abnormally dry.