July 11-17, 2018
Midwest Weekly Highlights - July 11-17, 2018
Hot Weather Continues
Temperatures were above normal across almost all of the Midwest during the period
(Figure 1). Only a few areas in east-central Illinois and west-central Indiana were near normal. Most of the region was only 1-3°F above normal however. Only areas in Missouri were 3-5°F above normal. Maximum temperatures averaged in the 90s across the state (Figure 2). Several dozen daily high maximum and high minimum temperature records were scattered across the region from the heat
(Figure 3).
Scattered Thunderstorms
A system brought scattered thunderstorms across the Midwest, with areas along the Mississippi River receiving the most rainfall (Figure 4). More than two inches fell in northern Minnesota into northwestern Wisconsin through the mornings of July 12
(Figure 5) and July 13 (Figure 6). Isolated amounts over five inches were recorded. Some of the totals for the two-day period included 7.61 inches in Mora, MN (Kanabec County), 4.92 inches near Cook, MN (St. Louis County) and 4.86 inches near Isle, MN (Aitkin County). As the system moved south, scattered amounts of 1-2 inches fell across the Mid-Mississippi River Valley. Areas that had the heaviest rainfall had more than twice the normal amount for the period
(Figure 7). More than 75 daily precipitation records were broken throughout the region (Figure 8). Meanwhile, most of Ohio River Valley, central Iowa and northern Missouri had less than three-fourths the normal amount.
Strong Thunderstorm Winds
Strong winds were accompanied by the scattered thunderstorms in the western half of the Midwest during the week
(Figure 9). Over 100 reports strong wind gusts and damage occurred. A wind gust of 75 mph was reported at the Davenport Municipal Airport (Scott County) on July 13. An injury also occurred near Gratiot, WI (Lafayette County) when a camper rolled over. A 71 mph wind gust was reported near Caseyville, IL (St. Clair County) on July 14. Several weak tornadoes were also reported in Beltrami County, MN on July 11 (Figure 10). One of these tornadoes briefly tracked across Lower Red Lake as a water spout.
Extreme Drought Expands in Missouri
Scattered thunderstorms evaded areas that needed rainfall the most in Missouri during the period (Figure 11). Coupled with hot temperatures, areas of extreme drought expanded in northern Missouri in the July 17 U.S. Drought Monitor. A small sliver of southern Davis County, IA was also included in the Extreme Drought category. Nearly 11 percent of Missouri was in Extreme Drought, while more than a quarter of the state was in either Severe or Extreme Drought.
Impacts on agriculture were being felt across the state. According to the USDA NASS Crop Progress Report for the week ending July 15, only 33 percent of corn and 40 percent of soybeans were rated good to excellent in the state. Only a quarter of the state had adequate topsoil and subsoil moisture, and only nine percent of pastures were in good condition. More than half the state had a stock water supply that was either short or very short.
Flash Drought Expands in Lower Michigan
Precipitation deficits in northeastern Lower Michigan contributed to the expansion of moderate drought in the July 17 U.S. Drought Monitor (Figure 12). Many of these areas have received less than half the normal amount of precipitation since June 1
(Figure 13), while temperatures have also been warmer than normal (Figure 14). Nearly half the state was considered abnormally dry or in drought. These conditions formed quickly, as only seven percent of the state was considered abnormally dry on July 3
(Figure 15).
-BJP-