Near Normal to Above Normal Temperatures

The July average temperature for the Midwest was 73.6°F, which was 0.9°F above the 1991-2020 normal. Statewide average temperatures ranged from near normal in Michigan and Illinois to 2.1°F above normal in Missouri and Kentucky (Figure 1). The warmest departures from normal were measured across the lower Midwest from Missouri to Kentucky, where numerous stations recorded a top ten warmest July. Murry, Kentucky, recorded the second warmest July over the past 94 years. Regionwide, 428 daily high temperature records were broken or tied (123 high maximum, 316 high minimum), and 139 daily low temperature records were broken or tied (31 low minimum, 112 low maximum).

Above Normal Precipitation

July precipitation was 4.12 inches for the Midwest, which was 0.02 inches above normal, or 101 percent of normal. Precipitation was highest in the southeast and lowest in the west (Figure 2). Statewide precipitation totals ranged from 1.11 inches below normal in Minnesota to 3.07 inches above normal in Kentucky (Figure 3). Kentucky had the fourth wettest July since 1895, with numerous cities reporting the wettest July on record. Buckhorn Lake, Kentucky, measured 17.51 inches for the month, exceeding the previous record by over 6 inches. Other notable monthly high precipitation records include Washington, Indiana (14.86 inches, records for 122 years) and St. Charles-Elm Point, Missouri (12.58 inches, records for 120 years). Conversely, in Minnesota, the University of St. Paul recorded the driest July in 62 years, with 1.37 inches. Marshfield, Missouri, had the 6th driest July since 1908 with 1.01 inches and a 22-day stretch with no measurable rainfall.

There were 438 daily high precipitation records broken or tied across the region in July, along with some shattered all-time records. Heavy rainfall in St. Louis, Missouri, on July 26 (see below), followed by several additional days of rain, resulted in a new 4-day rainfall record of 10.24 inches from July 25-July 28 (Figure 4). From July 26-28, Hazard, Kentucky, received 10.91 inches, setting a new 3-day rainfall record, with most falling in just a few hours on July 28 (see below) (Figure 5).

Flash Flooding in St. Louis on July 26

A cluster of training thunderstorms developed over the St. Louis, Missouri metropolitan area during the late evening hours on July 25 and persisted through the early afternoon on July 26. Continuous heavy rainfall, with rates periodically exceeding 2 inches per hour, soaked an area from northern Montgomery County (Missouri) to St. Clair County (Illinois) with 8-12 inches of water based on radar estimates and CoCoRaHS reports. The St. Louis-Lambert International Airport recorded a one-day total rainfall of 8.64 inches, making it the highest single-day rainfall measurement in the St. Louis area since record-keeping began in 1874. Flash flooding ensued, leading to numerous swift water rescues, flooded homes, closed interstate highways, and at least two fatalities.

Flash Flooding in Eastern Kentucky on July 28

Several large clusters of training thunderstorms passed over already-soaked ground in eastern Kentucky during the overnight hours from July 27 into July 28. Radar estimates indicate 5-10 inches of rain fell across a multi-county region from Laurel County eastward to Knott County on July 28. Rainfall rates, at times, exceeded 4 inches per hour. Hazard, Kentucky, set a new all-time single-day rainfall record with 8.55 inches, surpassing the previous record by 3.38 inches. Widespread catastrophic flash flooding resulted in over 1,300 people being rescued by helicopter and boat, and massive property and infrastructure damage occurred. There were 37 confirmed fatalities (as of Aug 3) across five counties (Breathitt-8, Clay-2, Knott-17, Letcher-3, and Perry-7).

Drought Update

Drought intensified across the Midwest throughout July (Figure 6). By month’s end, dryness and drought affected over 41 percent of the region. The greatest increases in intensity and spatial extent were in Missouri, where 50 percent of the state was in drought by late July, including 18 percent in extreme (D3) drought on the U.S. Drought Monitor map. Total corn crop loss was reported in several southwest Missouri counties, along with feed shortages for livestock and declining surface water supplies. Drought lingered in western Iowa and intensified in southern Minnesota, eastern Michigan, central Illinois, and western Kentucky in July. Drought improved and was eliminated from eastern Kentucky and southern Indiana.

Severe Weather

Regionwide, there were 875 preliminary storm reports (tornado, wind, and hail), which is well below the 2000-2021 median of 1,090 reports (Figure 7). There were about half as many tornadoes as typically seen in July and about 42 percent of median hail reports. Wind report counts were near the median.